diff --git a/exercises/00_hello_world/main.cpp b/exercises/00_hello_world/main.cpp index 8866f3c15..947ca5b37 100644 --- a/exercises/00_hello_world/main.cpp +++ b/exercises/00_hello_world/main.cpp @@ -1,4 +1,5 @@ #include "../exercise.h" +#include // READ: std streams // READ: 流修饰符 @@ -6,6 +7,6 @@ int main(int argc, char **argv) { // TODO: 在控制台输出 "Hello, InfiniTensor!" 并换行 - std::cout : "Hello, InfiniTensor!" + std::endl; + std::cout << "Hello, InfiniTensor!" << std::endl; return 0; } diff --git a/exercises/01_variable&add/main.cpp b/exercises/01_variable&add/main.cpp index 5014863fd..33a62b1b2 100644 --- a/exercises/01_variable&add/main.cpp +++ b/exercises/01_variable&add/main.cpp @@ -1,10 +1,12 @@ #include "../exercise.h" +#include // READ: 运算符 int main(int argc, char **argv) { // TODO: 补全变量定义并打印加法运算 - // x ? + int x = 5; + // std::cin >> x; std::cout << x << " + " << x << " = " << x + x << std::endl; return 0; } diff --git a/exercises/02_function/main.cpp b/exercises/02_function/main.cpp index b5eef7f28..50d58de3e 100644 --- a/exercises/02_function/main.cpp +++ b/exercises/02_function/main.cpp @@ -1,10 +1,12 @@ #include "../exercise.h" +#include // READ: 声明 // NOTICE: cppreference 中的示例中指出了复杂声明的解读法，建议认真阅读。 // NOTICE: 补充由内而外读法的机翻解释 // TODO: 在这里声明函数 +int add(int a, int b); int main(int argc, char **argv) { ASSERT(add(123, 456) == 123 + 456, "add(123, 456) should be 123 + 456"); @@ -16,4 +18,5 @@ int main(int argc, char **argv) { int add(int a, int b) { // TODO: 补全函数定义，但不要移动代码行 + return a + b; } diff --git a/exercises/03_argument¶meter/main.cpp b/exercises/03_argument¶meter/main.cpp index 7fb5d3c2f..76136eae6 100644 --- a/exercises/03_argument¶meter/main.cpp +++ b/exercises/03_argument¶meter/main.cpp @@ -8,19 +8,19 @@ void func(int); // TODO: 为下列 ASSERT 填写正确的值 int main(int argc, char **argv) { auto arg = 99; - ASSERT(arg == ?, "arg should be ?"); + ASSERT(arg == 99, "arg should be ?"); std::cout << "befor func call: " << arg << std::endl; func(arg); - ASSERT(arg == ?, "arg should be ?"); + ASSERT(arg == 99, "arg should be ?"); std::cout << "after func call: " << arg << std::endl; return 0; } // TODO: 为下列 ASSERT 填写正确的值 void func(int param) { - ASSERT(param == ?, "param should be ?"); + ASSERT(param == 99, "param should be ?"); std::cout << "befor add: " << param << std::endl; param += 1; - ASSERT(param == ?, "param should be ?"); + ASSERT(param == 100, "param should be ?"); std::cout << "after add: " << param << std::endl; } diff --git a/exercises/04_static/main.cpp b/exercises/04_static/main.cpp index f107762fa..64f417694 100644 --- a/exercises/04_static/main.cpp +++ b/exercises/04_static/main.cpp @@ -10,10 +10,10 @@ static int func(int param) { int main(int argc, char **argv) { // TODO: 将下列 `?` 替换为正确的数字 - ASSERT(func(5) == ?, "static variable value incorrect"); - ASSERT(func(4) == ?, "static variable value incorrect"); - ASSERT(func(3) == ?, "static variable value incorrect"); - ASSERT(func(2) == ?, "static variable value incorrect"); - ASSERT(func(1) == ?, "static variable value incorrect"); + ASSERT(func(5) == 5, "static variable value incorrect"); + ASSERT(func(4) == 6, "static variable value incorrect"); + ASSERT(func(3) == 7, "static variable value incorrect"); + ASSERT(func(2) == 8, "static variable value incorrect"); + ASSERT(func(1) == 9, "static variable value incorrect"); return 0; } diff --git a/exercises/05_constexpr/main.cpp b/exercises/05_constexpr/main.cpp index d1db6c9d8..91e5414fd 100644 --- a/exercises/05_constexpr/main.cpp +++ b/exercises/05_constexpr/main.cpp @@ -1,4 +1,23 @@ #include "../exercise.h" +#include + +/* +// Performance improved version: Reduce time complexity from O(2^n) to O(n) +constexpr unsigned long long fibonacci2(int n) { + int i = 2; + int f_1 = 1; + int f_2 = 0; + int f = 0; + do { + f = f_1 + f_2; + f_2 = f_1; + f_1 = f; + i++; + } while (i <= n); + unsigned long long result = f; + return result; +} +*/ constexpr unsigned long long fibonacci(int i) { switch (i) { @@ -15,12 +34,15 @@ int main(int argc, char **argv) { constexpr auto FIB20 = fibonacci(20); ASSERT(FIB20 == 6765, "fibonacci(20) should be 6765"); std::cout << "fibonacci(20) = " << FIB20 << std::endl; + // std::cout << "fibonacci(20) = " << fibonacci(20) << std::endl; + // std::cout << "fibonacci2(20) = " << fibonacci2(20) << std::endl; // TODO: 观察错误信息，修改一处，使代码编译运行 // PS: 编译运行，但是不一定能算出结果…… - constexpr auto ANS_N = 90; - constexpr auto ANS = fibonacci(ANS_N); + constexpr auto ANS_N = 10; + auto ANS = fibonacci(ANS_N); std::cout << "fibonacci(" << ANS_N << ") = " << ANS << std::endl; + // std::cout << "fibonacci2(90) = " << fibonacci2(90) << std::endl; return 0; } diff --git a/exercises/06_array/main.cpp b/exercises/06_array/main.cpp index 61ed99ec0..05afbb8d3 100644 --- a/exercises/06_array/main.cpp +++ b/exercises/06_array/main.cpp @@ -11,13 +11,13 @@ unsigned long long fibonacci(int i) { return 1; default: // TODO: 补全三目表达式缺失的部分 - return ? : (arr[i] = fibonacci(i - 1) + fibonacci(i - 2)); + return (arr[i]) != 0 ? arr[i] : (arr[i] = fibonacci(i - 1) + fibonacci(i - 2)); } } int main(int argc, char **argv) { // TODO: 为此 ASSERT 填写正确的值 - ASSERT(sizeof(arr) == ?, "sizeof array is size of all its elements"); + ASSERT(sizeof(arr) == 90 * sizeof(unsigned long long), "sizeof array is size of all its elements"); // ---- 不要修改以下代码 ---- ASSERT(fibonacci(2) == 1, "fibonacci(2) should be 1"); ASSERT(fibonacci(20) == 6765, "fibonacci(20) should be 6765"); diff --git a/exercises/07_loop/main.cpp b/exercises/07_loop/main.cpp index 44fd835cd..c54efe601 100644 --- a/exercises/07_loop/main.cpp +++ b/exercises/07_loop/main.cpp @@ -1,4 +1,5 @@ #include "../exercise.h" +#include // TODO: 改正函数实现，实现正确的缓存优化斐波那契计算 // THINk: 这个函数是一个纯函数（pure function）吗？ @@ -6,8 +7,15 @@ static unsigned long long fibonacci(int i) { // TODO: 为缓存设置正确的初始值 static unsigned long long cache[96], cached; + + if (cached == 0) { + cache[0] = 0ULL; + cache[1] = 1ULL; + cached = 2; + } // TODO: 设置正确的循环条件 - for (; false; ++cached) { + // static_cast(i) is to resolve the warning different signedness: ‘long long unsigned int’ and ‘int’ + for (; cached <= static_cast(i); ++cached) { cache[cached] = cache[cached - 1] + cache[cached - 2]; } return cache[i]; diff --git a/exercises/08_pointer/main.cpp b/exercises/08_pointer/main.cpp index ba37173f5..91f45388e 100644 --- a/exercises/08_pointer/main.cpp +++ b/exercises/08_pointer/main.cpp @@ -3,8 +3,15 @@ // READ: 数组向指针退化 bool is_fibonacci(int *ptr, int len, int stride) { ASSERT(len >= 3, "`len` should be at least 3"); + if (stride <= 0) return false; // basic guard // TODO: 编写代码判断从 ptr 开始，每 stride 个元素取 1 个元素，组成长度为 n 的数列是否满足 // arr[i + 2] = arr[i] + arr[i + 1] + for (int k = 0; k <= len - 3; ++k) { + int a0 = ptr[k *stride]; + int a1 = ptr[(k + 1) * stride]; + int a2 = ptr[(k + 2) * stride]; + if (a2 != a0 + a1) return false; + } return true; } diff --git a/exercises/09_enum&union/main.cpp b/exercises/09_enum&union/main.cpp index 3f2cec768..6d82104c0 100644 --- a/exercises/09_enum&union/main.cpp +++ b/exercises/09_enum&union/main.cpp @@ -37,6 +37,11 @@ ColorEnum convert_by_pun(Color c) { TypePun pun; // TODO: 补全类型双关转换 + pun.c = c; + // Well-defined conversion: Color(enum class,int) -> int -> unsigned char -> ColorEnum + pun.e = static_cast( + static_cast( + static_cast>(pun.c))); return pun.e; } diff --git a/exercises/10_trivial/main.cpp b/exercises/10_trivial/main.cpp index 6ba23e48e..fe367e665 100644 --- a/exercises/10_trivial/main.cpp +++ b/exercises/10_trivial/main.cpp @@ -1,4 +1,5 @@ #include "../exercise.h" +#include // READ: Trivial type @@ -8,18 +9,26 @@ struct FibonacciCache { }; // TODO: 实现正确的缓存优化斐波那契计算 -static unsigned long long fibonacci(FibonacciCache &cache, int i) { - for (; false; ++cached) { - cache[cached] = cache[cached - 1] + cache[cached - 2]; +static unsigned long long fibonacci(FibonacciCache &fc, int i) { + ASSERT(i >= 0 && i < 16, "i out of range for 16-entry cache") + // Guard: initialize F(0)=0, F(1)=1, and cached + std::cout << fc.cached << std::endl; + ASSERT(fc.cached >= 0 && fc.cached < 16, "fc.cached is out of range for 16 entry cache") + if (fc.cached < 2) fc.cached = 2; + if (fc.cache[0] != 0) fc.cache[0] = 0ULL; + if (fc.cache[1] != 1) fc.cache[1] = 1ULL; + // Fill in the Fibonacci variables + for (; fc.cached <= i; ++fc.cached) { + fc.cache[fc.cached] = fc.cache[fc.cached - 1] + fc.cache[fc.cached - 2]; } - return cache.cache[i]; + return fc.cache[i]; } int main(int argc, char **argv) { // TODO: 初始化缓存结构体，使计算正确 // NOTICE: C/C++ 中，读取未初始化的变量（包括结构体变量）是未定义行为 // READ: 初始化的各种写法 - FibonacciCache fib; + FibonacciCache fib{{0ULL, 1ULL}, 2}; ASSERT(fibonacci(fib, 10) == 55, "fibonacci(10) should be 55"); std::cout << "fibonacci(10) = " << fibonacci(fib, 10) << std::endl; return 0; diff --git a/exercises/11_method/main.cpp b/exercises/11_method/main.cpp index 0e08e0a36..e883c55d7 100644 --- a/exercises/11_method/main.cpp +++ b/exercises/11_method/main.cpp @@ -1,4 +1,5 @@ #include "../exercise.h" +#include struct Fibonacci { unsigned long long cache[128]; @@ -6,7 +7,15 @@ struct Fibonacci { // TODO: 实现正确的缓存优化斐波那契计算 unsigned long long get(int i) { - for (; false; ++cached) { + ASSERT(i >= 0 && i < 128, "i out of range for 128-entry cache"); + + // Guard: initialize F(0), F(1) and minimum index: + if (cached < 2 || cached >= 128) cached = 2; + if (cache[0] != 0) cache[0] = 0ULL; + if (cache[1] != 1) cache[1] = 1ULL; + + // calculate Fibonacci + for (; cached <= i; ++cached) { cache[cached] = cache[cached - 1] + cache[cached - 2]; } return cache[i]; @@ -15,7 +24,7 @@ struct Fibonacci { int main(int argc, char **argv) { // TODO: 初始化缓存结构体，使计算正确 - Fibonacci fib; + Fibonacci fib{{0, 1}, 2}; ASSERT(fib.get(10) == 55, "fibonacci(10) should be 55"); std::cout << "fibonacci(10) = " << fib.get(10) << std::endl; return 0; diff --git a/exercises/12_method_const/main.cpp b/exercises/12_method_const/main.cpp index 5521be4da..841eb7d04 100644 --- a/exercises/12_method_const/main.cpp +++ b/exercises/12_method_const/main.cpp @@ -1,11 +1,13 @@ #include "../exercise.h" +#include // READ: 有 cv 限定符的成员函数 struct Fibonacci { int numbers[11]; // TODO: 修改方法签名和实现，使测试通过 - int get(int i) { + constexpr int get(int i) const{ + return numbers[i]; } }; diff --git a/exercises/13_class/main.cpp b/exercises/13_class/main.cpp index 9afa98c5b..316b4f94b 100644 --- a/exercises/13_class/main.cpp +++ b/exercises/13_class/main.cpp @@ -14,11 +14,15 @@ class Fibonacci { public: // TODO: 实现构造器 - // Fibonacci() + Fibonacci() : cache{0, 1}, cached(2) {} // TODO: 实现正确的缓存优化斐波那契计算 size_t get(int i) { - for (; false; ++cached) { + // Guard: initialize cache[0] + cache[1] and cached >= 2 + cache[0] = 0ULL; + cache[1] = 1ULL; + if (cached < 2) cached = 2; + for (; cached <= i; ++cached) { cache[cached] = cache[cached - 1] + cache[cached - 2]; } return cache[i]; @@ -28,7 +32,7 @@ class Fibonacci { int main(int argc, char **argv) { // 现在类型拥有无参构造器，声明时会直接调用。 // 这个写法不再是未定义行为了。 - Fibonacci fib; + Fibonacci fib{}; ASSERT(fib.get(10) == 55, "fibonacci(10) should be 55"); std::cout << "fibonacci(10) = " << fib.get(10) << std::endl; return 0; diff --git a/exercises/14_class_destruct/main.cpp b/exercises/14_class_destruct/main.cpp index 42150e8ca..04b54d355 100644 --- a/exercises/14_class_destruct/main.cpp +++ b/exercises/14_class_destruct/main.cpp @@ -1,4 +1,5 @@ #include "../exercise.h" +#include // READ: 析构函数 // READ: RAII @@ -11,14 +12,20 @@ class DynFibonacci { public: // TODO: 实现动态设置容量的构造器 - DynFibonacci(int capacity): cache(new ?), cached(?) {} + DynFibonacci(int capacity) + : cache(new size_t[capacity]{}), cached(2) { + cache[0] = 0; + cache[1] = 1; + } // TODO: 实现析构器，释放缓存空间 - ~DynFibonacci(); + ~DynFibonacci() { + delete[] cache; + }; // TODO: 实现正确的缓存优化斐波那契计算 size_t get(int i) { - for (; false; ++cached) { + for (; cached <= i; ++cached) { cache[cached] = cache[cached - 1] + cache[cached - 2]; } return cache[i]; diff --git a/exercises/15_class_clone/main.cpp b/exercises/15_class_clone/main.cpp index f74b70391..10011588c 100644 --- a/exercises/15_class_clone/main.cpp +++ b/exercises/15_class_clone/main.cpp @@ -1,4 +1,6 @@ #include "../exercise.h" +#include +#include // READ: 复制构造函数 // READ: 函数定义（显式弃置） @@ -10,17 +12,26 @@ class DynFibonacci { public: // TODO: 实现动态设置容量的构造器 - DynFibonacci(int capacity): cache(new ?), cached(?) {} + DynFibonacci(int capacity): cache(new size_t[capacity]{}), cached(2) { + ASSERT(capacity >= 2, "capacity must be at least 2"); + cache[0] = 0; cache[1] = 1; cached = 2; + } // TODO: 实现复制构造器 - DynFibonacci(DynFibonacci const &) = delete; + DynFibonacci(DynFibonacci const &other) + : cache(new size_t[other.cached + 1]{}), cached(other.cached) { + std::copy(other.cache, other.cache + other.cached + 1, cache); + } + // TODO: 实现析构器，释放缓存空间 - ~DynFibonacci(); + ~DynFibonacci() { + delete[] cache; + } // TODO: 实现正确的缓存优化斐波那契计算 size_t get(int i) { - for (; false; ++cached) { + for (; cached <= i; ++cached) { cache[cached] = cache[cached - 1] + cache[cached - 2]; } return cache[i]; @@ -40,6 +51,7 @@ class DynFibonacci { int main(int argc, char **argv) { DynFibonacci fib(12); + // std::cout << fib.get(10) << std::endl; ASSERT(fib.get(10) == 55, "fibonacci(10) should be 55"); DynFibonacci const fib_ = fib; ASSERT(fib_.get(10) == fib.get(10), "Object cloned"); diff --git a/exercises/16_class_move/main.cpp b/exercises/16_class_move/main.cpp index 8d2c421da..ed937988e 100644 --- a/exercises/16_class_move/main.cpp +++ b/exercises/16_class_move/main.cpp @@ -15,21 +15,36 @@ class DynFibonacci { public: // TODO: 实现动态设置容量的构造器 - DynFibonacci(int capacity): cache(new ?), cached(?) {} + DynFibonacci(int capacity): cache(new size_t[capacity]{0, 1}), cached(2) {} // TODO: 实现移动构造器 - DynFibonacci(DynFibonacci &&) noexcept = delete; + DynFibonacci(DynFibonacci &&other) noexcept + : cache(other.cache), cached(other.cached) { + other.cache = nullptr; + other.cached = 0; + } // TODO: 实现移动赋值 // NOTICE: ⚠ 注意移动到自身问题 ⚠ - DynFibonacci &operator=(DynFibonacci &&) noexcept = delete; + DynFibonacci &operator=(DynFibonacci &&other) noexcept { + if (this != &other) { + delete[] cache; + cache = other.cache; + cached = other.cached; + other.cache = nullptr; + other.cached = 0; + } + return *this; + } // TODO: 实现析构器，释放缓存空间 - ~DynFibonacci(); + ~DynFibonacci() { + delete[] cache; + } // TODO: 实现正确的缓存优化斐波那契计算 size_t operator[](int i) { - for (; false; ++cached) { + for (; cached <= i; ++cached) { cache[cached] = cache[cached - 1] + cache[cached - 2]; } return cache[i]; @@ -59,7 +74,10 @@ int main(int argc, char **argv) { DynFibonacci fib1(12); fib0 = std::move(fib1); + #pragma GCC diagnostic push + #pragma GCC diagnostic ignored "-Wself-move" fib0 = std::move(fib0); + #pragma GCC diagnostic pop ASSERT(fib0[10] == 55, "fibonacci(10) should be 55"); return 0; diff --git a/exercises/17_class_derive/main.cpp b/exercises/17_class_derive/main.cpp index 819ae72fc..0c245df4f 100644 --- a/exercises/17_class_derive/main.cpp +++ b/exercises/17_class_derive/main.cpp @@ -50,9 +50,9 @@ int main(int argc, char **argv) { B b = B(3); // TODO: 补全三个类型的大小 - static_assert(sizeof(X) == ?, "There is an int in X"); - static_assert(sizeof(A) == ?, "There is an int in A"); - static_assert(sizeof(B) == ?, "B is an A with an X"); + static_assert(sizeof(X) == 4, "There is an int in X"); + static_assert(sizeof(A) == 4, "There is an int in A"); + static_assert(sizeof(B) == 8, "B is an A with an X"); i = 0; std::cout << std::endl diff --git a/exercises/18_class_virtual/main.cpp b/exercises/18_class_virtual/main.cpp index ac6382413..344709e4c 100644 --- a/exercises/18_class_virtual/main.cpp +++ b/exercises/18_class_virtual/main.cpp @@ -42,38 +42,38 @@ int main(int argc, char **argv) { C c; D d; - ASSERT(a.virtual_name() == '?', MSG); - ASSERT(b.virtual_name() == '?', MSG); - ASSERT(c.virtual_name() == '?', MSG); - ASSERT(d.virtual_name() == '?', MSG); - ASSERT(a.direct_name() == '?', MSG); - ASSERT(b.direct_name() == '?', MSG); - ASSERT(c.direct_name() == '?', MSG); - ASSERT(d.direct_name() == '?', MSG); + ASSERT(a.virtual_name() == 'A', MSG); + ASSERT(b.virtual_name() == 'B', MSG); + ASSERT(c.virtual_name() == 'C', MSG); + ASSERT(d.virtual_name() == 'C', MSG); + ASSERT(a.direct_name() == 'A', MSG); + ASSERT(b.direct_name() == 'B', MSG); + ASSERT(c.direct_name() == 'C', MSG); + ASSERT(d.direct_name() == 'D', MSG); A &rab = b; B &rbc = c; C &rcd = d; - ASSERT(rab.virtual_name() == '?', MSG); - ASSERT(rbc.virtual_name() == '?', MSG); - ASSERT(rcd.virtual_name() == '?', MSG); - ASSERT(rab.direct_name() == '?', MSG); - ASSERT(rbc.direct_name() == '?', MSG); - ASSERT(rcd.direct_name() == '?', MSG); + ASSERT(rab.virtual_name() == 'B', MSG); + ASSERT(rbc.virtual_name() == 'C', MSG); + ASSERT(rcd.virtual_name() == 'C', MSG); + ASSERT(rab.direct_name() == 'A', MSG); + ASSERT(rbc.direct_name() == 'B', MSG); + ASSERT(rcd.direct_name() == 'C', MSG); A &rac = c; B &rbd = d; - ASSERT(rac.virtual_name() == '?', MSG); - ASSERT(rbd.virtual_name() == '?', MSG); - ASSERT(rac.direct_name() == '?', MSG); - ASSERT(rbd.direct_name() == '?', MSG); + ASSERT(rac.virtual_name() == 'C', MSG); + ASSERT(rbd.virtual_name() == 'C', MSG); + ASSERT(rac.direct_name() == 'A', MSG); + ASSERT(rbd.direct_name() == 'B', MSG); A &rad = d; - ASSERT(rad.virtual_name() == '?', MSG); - ASSERT(rad.direct_name() == '?', MSG); + ASSERT(rad.virtual_name() == 'C', MSG); + ASSERT(rad.direct_name() == 'A', MSG); return 0; } diff --git a/exercises/19_class_virtual_destruct/main.cpp b/exercises/19_class_virtual_destruct/main.cpp index cdd54f74f..b1a852588 100644 --- a/exercises/19_class_virtual_destruct/main.cpp +++ b/exercises/19_class_virtual_destruct/main.cpp @@ -1,16 +1,17 @@ #include "../exercise.h" +#include // READ: 静态字段 // READ: 虚析构函数 struct A { // TODO: 正确初始化静态字段 - static int num_a = 0; + static int num_a; A() { ++num_a; } - ~A() { + virtual ~A() { --num_a; } @@ -20,12 +21,12 @@ struct A { }; struct B final : public A { // TODO: 正确初始化静态字段 - static int num_b = 0; + static int num_b; B() { ++num_b; } - ~B() { + ~B() override { --num_b; } @@ -34,13 +35,16 @@ struct B final : public A { } }; +int A::num_a = 0; +int B::num_b = 0; + int main(int argc, char **argv) { auto a = new A; auto b = new B; - ASSERT(A::num_a == ?, "Fill in the correct value for A::num_a"); - ASSERT(B::num_b == ?, "Fill in the correct value for B::num_b"); - ASSERT(a->name() == '?', "Fill in the correct value for a->name()"); - ASSERT(b->name() == '?', "Fill in the correct value for b->name()"); + ASSERT(A::num_a == 2, "Fill in the correct value for A::num_a"); + ASSERT(B::num_b == 1, "Fill in the correct value for B::num_b"); + ASSERT(a->name() == 'A', "Fill in the correct value for a->name()"); + ASSERT(b->name() == 'B', "Fill in the correct value for b->name()"); delete a; delete b; @@ -48,13 +52,13 @@ int main(int argc, char **argv) { ASSERT(B::num_b == 0, "Every B was destroyed"); A *ab = new B;// 派生类指针可以随意转换为基类指针 - ASSERT(A::num_a == ?, "Fill in the correct value for A::num_a"); - ASSERT(B::num_b == ?, "Fill in the correct value for B::num_b"); - ASSERT(ab->name() == '?', "Fill in the correct value for ab->name()"); + ASSERT(A::num_a == 1, "Fill in the correct value for A::num_a"); + ASSERT(B::num_b == 1, "Fill in the correct value for B::num_b"); + ASSERT(ab->name() == 'B', "Fill in the correct value for ab->name()"); // TODO: 基类指针无法随意转换为派生类指针，补全正确的转换语句 - B &bb = *ab; - ASSERT(bb.name() == '?', "Fill in the correct value for bb->name()"); + B &bb = dynamic_cast(*ab); + ASSERT(bb.name() == 'B', "Fill in the correct value for bb->name()"); // TODO: ---- 以下代码不要修改，通过改正类定义解决编译问题 ---- delete ab;// 通过指针可以删除指向的对象，即使是多态对象 diff --git a/exercises/20_function_template/main.cpp b/exercises/20_function_template/main.cpp index cb6d978d3..3176c596b 100644 --- a/exercises/20_function_template/main.cpp +++ b/exercises/20_function_template/main.cpp @@ -1,10 +1,19 @@ #include "../exercise.h" +#include // std::abs // READ: 函数模板 // TODO: 将这个函数模板化 +/* +// The original function: int plus(int a, int b) { return a + b; } +// New template function: +*/ +template +constexpr T plus(T a, T b) { + return a + b; +} int main(int argc, char **argv) { ASSERT(plus(1, 2) == 3, "Plus two int"); @@ -14,7 +23,8 @@ int main(int argc, char **argv) { ASSERT(plus(1.25f, 2.5f) == 3.75f, "Plus two float"); ASSERT(plus(1.25, 2.5) == 3.75, "Plus two double"); // TODO: 修改判断条件使测试通过 - ASSERT(plus(0.1, 0.2) == 0.3, "How to make this pass?"); + constexpr double eps = 1e-12; + ASSERT(std::abs(plus(0.1, 0.2) - 0.3) < eps, "How to make this pass?"); return 0; } diff --git a/exercises/21_runtime_datatype/main.cpp b/exercises/21_runtime_datatype/main.cpp index 9c4bf376a..5888a42a1 100644 --- a/exercises/21_runtime_datatype/main.cpp +++ b/exercises/21_runtime_datatype/main.cpp @@ -18,13 +18,28 @@ struct TaggedUnion { }; // TODO: 将这个函数模板化用于 sigmoid_dyn +/* +// The old function float sigmoid(float x) { return 1 / (1 + std::exp(-x)); } +// The new function with template: +*/ +template +constexpr T sigmoid(T x) { + return T(1) / (T(1) + std::exp(-x)); +} TaggedUnion sigmoid_dyn(TaggedUnion x) { TaggedUnion ans{x.type}; - // TODO: 根据 type 调用 sigmoid + switch (x.type) { + case DataType::Float: + ans.f = sigmoid(x.f); + break; + case DataType::Double: + ans.d = sigmoid(x.d); + break; + } return ans; } diff --git a/exercises/22_class_template/main.cpp b/exercises/22_class_template/main.cpp index d4985d904..ca48205c3 100644 --- a/exercises/22_class_template/main.cpp +++ b/exercises/22_class_template/main.cpp @@ -10,6 +10,10 @@ struct Tensor4D { Tensor4D(unsigned int const shape_[4], T const *data_) { unsigned int size = 1; // TODO: 填入正确的 shape 并计算 size + for (int k = 0; k < 4; k++) { + shape[k] = shape_[k]; + size *= shape[k]; + } data = new T[size]; std::memcpy(data, data_, size * sizeof(T)); } @@ -28,6 +32,43 @@ struct Tensor4D { // 则 `this` 与 `others` 相加时，3 个形状为 `[1, 2, 1, 4]` 的子张量各自与 `others` 对应项相加。 Tensor4D &operator+=(Tensor4D const &others) { // TODO: 实现单向广播的加法 + // 1) Check boardcastability per dimension + for (int k = 0; k < 4; ++k) { + ASSERT(others.shape[k] == shape[k] || others.shape[k] == 1, + "Shapes are not broadcast-compatible"); + } + + // 2) Precompute strids (row-major, last axis fastest) + unsigned int stride_other[4]; + { + unsigned int s = 1; + for (int k = 3; k >= 0; --k) { + stride_other[k] = s; + s *= others.shape[k]; + } + } + + // 3) For each element of self, map to others (use 0 index when others.shape[k]==1) + unsigned int total = shape[0] * shape[1] * shape[2] * shape[3]; + for (unsigned int i = 0; i < total; ++i) { + // Decode i -> 4D coords in self + unsigned int idx = i; + unsigned int coord[4]; + for (int k = 3; k >= 0; --k) { + coord[k] = idx % shape[k]; + idx /= shape[k]; + } + + // Map coords to other's linear index (broadcast where dim==1) + unsigned int j = 0; + for (int k = 0; k < 4; ++k) { + unsigned int ck = (others.shape[k] == 1) ? 0u : coord[k]; + j += ck * stride_other[k]; + } + + data[i] += others.data[j]; + } + return *this; } }; diff --git a/exercises/23_template_const/main.cpp b/exercises/23_template_const/main.cpp index e0105e168..6a288cae0 100644 --- a/exercises/23_template_const/main.cpp +++ b/exercises/23_template_const/main.cpp @@ -11,6 +11,10 @@ struct Tensor { Tensor(unsigned int const shape_[N]) { unsigned int size = 1; // TODO: 填入正确的 shape 并计算 size + for (unsigned int i = 0; i < N; i++) { + shape[i] = shape_[i]; + size *= shape[i]; + } data = new T[size]; std::memset(data, 0, size * sizeof(T)); } @@ -35,6 +39,7 @@ struct Tensor { for (unsigned int i = 0; i < N; ++i) { ASSERT(indices[i] < shape[i], "Invalid index"); // TODO: 计算 index + index = index * shape[i] + indices[i]; } return index; } diff --git a/exercises/24_std_array/main.cpp b/exercises/24_std_array/main.cpp index c29718d9d..72f10b3e3 100644 --- a/exercises/24_std_array/main.cpp +++ b/exercises/24_std_array/main.cpp @@ -8,21 +8,21 @@ int main(int argc, char **argv) { { std::array arr{{1, 2, 3, 4, 5}}; - ASSERT(arr.size() == ?, "Fill in the correct value."); - ASSERT(sizeof(arr) == ?, "Fill in the correct value."); + ASSERT(arr.size() == 5, "Fill in the correct value."); + ASSERT(sizeof(arr) == 5 * sizeof(int), "Fill in the correct value."); int ans[]{1, 2, 3, 4, 5}; - ASSERT(std::memcmp(arr.?, ans, ?) == 0, "Fill in the correct values."); + ASSERT(std::memcmp(arr.data(), ans, sizeof(ans)==0) == 0, "Fill in the correct values."); } { std::array arr; - ASSERT(arr.size() == ?, "Fill in the correct value."); - ASSERT(sizeof(arr) == ?, "Fill in the correct value."); + ASSERT(arr.size() == 8, "Fill in the correct value."); + ASSERT(sizeof(arr) == 8 * sizeof(double), "Fill in the correct value."); } { std::array arr{"Hello, InfiniTensor!"}; - ASSERT(arr.size() == ?, "Fill in the correct value."); - ASSERT(sizeof(arr) == ?, "Fill in the correct value."); - ASSERT(std::strcmp(arr.?, "Hello, InfiniTensor!") == 0, "Fill in the correct value."); + ASSERT(arr.size() == 21, "Fill in the correct value."); + ASSERT(sizeof(arr) == 21 * sizeof(char), "Fill in the correct value."); + ASSERT(std::strcmp(arr.data(), "Hello, InfiniTensor!") == 0, "Fill in the correct value."); } return 0; } diff --git a/exercises/25_std_vector/main.cpp b/exercises/25_std_vector/main.cpp index f9e41bb78..805635c37 100644 --- a/exercises/25_std_vector/main.cpp +++ b/exercises/25_std_vector/main.cpp @@ -8,81 +8,81 @@ int main(int argc, char **argv) { { std::vector vec{1, 2, 3, 4, 5}; - ASSERT(vec.size() == ?, "Fill in the correct value."); + ASSERT(vec.size() == 5, "Fill in the correct value."); // THINK: `std::vector` 的大小是什么意思？与什么有关？ - ASSERT(sizeof(vec) == ?, "Fill in the correct value."); + ASSERT(sizeof(vec) == 24, "Fill in the correct value."); int ans[]{1, 2, 3, 4, 5}; - ASSERT(std::memcmp(vec.?, ans, sizeof(ans)) == 0, "Fill in the correct values."); + ASSERT(std::memcmp(vec.data(), ans, sizeof(ans)) == 0, "Fill in the correct values."); } { std::vector vec{1, 2, 3, 4, 5}; { - ASSERT(vec.size() == ?, "Fill in the correct value."); - ASSERT(sizeof(vec) == ?, "Fill in the correct value."); + ASSERT(vec.size() == 5, "Fill in the correct value."); + ASSERT(sizeof(vec) == 24, "Fill in the correct value."); double ans[]{1, 2, 3, 4, 5}; - ASSERT(std::memcmp(vec.?, ans, sizeof(ans)) == 0, "Fill in the correct values."); + ASSERT(std::memcmp(vec.data(), ans, sizeof(ans)) == 0, "Fill in the correct values."); } { vec.push_back(6); - ASSERT(vec.size() == ?, "Fill in the correct value."); - ASSERT(sizeof(vec) == ?, "Fill in the correct value."); + ASSERT(vec.size() == 6, "Fill in the correct value."); + ASSERT(sizeof(vec) == 24, "Fill in the correct value."); vec.pop_back(); - ASSERT(vec.size() == ?, "Fill in the correct value."); - ASSERT(sizeof(vec) == ?, "Fill in the correct value."); + ASSERT(vec.size() == 5, "Fill in the correct value."); + ASSERT(sizeof(vec) == 24, "Fill in the correct value."); } { vec[4] = 6; - ASSERT(vec[0] == ?, "Fill in the correct value."); - ASSERT(vec[1] == ?, "Fill in the correct value."); - ASSERT(vec[2] == ?, "Fill in the correct value."); - ASSERT(vec[3] == ?, "Fill in the correct value."); - ASSERT(vec[4] == ?, "Fill in the correct value."); + ASSERT(vec[0] == 1, "Fill in the correct value."); + ASSERT(vec[1] == 2, "Fill in the correct value."); + ASSERT(vec[2] == 3, "Fill in the correct value."); + ASSERT(vec[3] == 4, "Fill in the correct value."); + ASSERT(vec[4] == 6, "Fill in the correct value."); } { // THINK: `std::vector` 插入删除的时间复杂度是什么？ - vec.insert(?, 1.5); + vec.insert(vec.begin() + 1, 1.5); ASSERT((vec == std::vector{1, 1.5, 2, 3, 4, 6}), "Make this assertion pass."); - vec.erase(?); + vec.erase(vec.begin() + 3); ASSERT((vec == std::vector{1, 1.5, 2, 4, 6}), "Make this assertion pass."); } { vec.shrink_to_fit(); - ASSERT(vec.capacity() == ?, "Fill in the correct value."); + ASSERT(vec.capacity() == 5, "Fill in the correct value."); vec.clear(); ASSERT(vec.empty(), "`vec` is empty now."); - ASSERT(vec.size() == ?, "Fill in the correct value."); - ASSERT(vec.capacity() == ?, "Fill in the correct value."); + ASSERT(vec.size() == 0, "Fill in the correct value."); + ASSERT(vec.capacity() == 5, "Fill in the correct value."); } } { - std::vector vec(?, ?); // TODO: 调用正确的构造函数 + std::vector vec(48, 'z'); // TODO: 调用正确的构造函数 ASSERT(vec[0] == 'z', "Make this assertion pass."); ASSERT(vec[47] == 'z', "Make this assertion pass."); ASSERT(vec.size() == 48, "Make this assertion pass."); - ASSERT(sizeof(vec) == ?, "Fill in the correct value."); + ASSERT(sizeof(vec) == 24, "Fill in the correct value."); { auto capacity = vec.capacity(); vec.resize(16); - ASSERT(vec.size() == ?, "Fill in the correct value."); - ASSERT(vec.capacity() == ?, "Fill in a correct identifier."); + ASSERT(vec.size() == 16, "Fill in the correct value."); + ASSERT(vec.capacity() == capacity, "Fill in a correct identifier."); } { vec.reserve(256); - ASSERT(vec.size() == ?, "Fill in the correct value."); - ASSERT(vec.capacity() == ?, "Fill in the correct value."); + ASSERT(vec.size() == 16, "Fill in the correct value."); + ASSERT(vec.capacity() == 256, "Fill in the correct value."); } { vec.push_back('a'); vec.push_back('b'); vec.push_back('c'); vec.push_back('d'); - ASSERT(vec.size() == ?, "Fill in the correct value."); - ASSERT(vec.capacity() == ?, "Fill in the correct value."); - ASSERT(vec[15] == ?, "Fill in the correct value."); - ASSERT(vec[?] == 'a', "Fill in the correct value."); - ASSERT(vec[?] == 'b', "Fill in the correct value."); - ASSERT(vec[?] == 'c', "Fill in the correct value."); - ASSERT(vec[?] == 'd', "Fill in the correct value."); + ASSERT(vec.size() == 20, "Fill in the correct value."); + ASSERT(vec.capacity() == 256, "Fill in the correct value."); + ASSERT(vec[15] == 'z', "Fill in the correct value."); + ASSERT(vec[16] == 'a', "Fill in the correct value."); + ASSERT(vec[17] == 'b', "Fill in the correct value."); + ASSERT(vec[18] == 'c', "Fill in the correct value."); + ASSERT(vec[19] == 'd', "Fill in the correct value."); } } diff --git a/exercises/26_std_vector_bool/main.cpp b/exercises/26_std_vector_bool/main.cpp index b4ab4f9c4..15103c20e 100644 --- a/exercises/26_std_vector_bool/main.cpp +++ b/exercises/26_std_vector_bool/main.cpp @@ -6,29 +6,29 @@ // TODO: 将下列 `?` 替换为正确的代码 int main(int argc, char **argv) { - std::vector vec(?, ?);// TODO: 正确调用构造函数 + std::vector vec(100, true);// TODO: 正确调用构造函数 ASSERT(vec[0], "Make this assertion pass."); ASSERT(vec[99], "Make this assertion pass."); ASSERT(vec.size() == 100, "Make this assertion pass."); // NOTICE: 平台相关！注意 CI:Ubuntu 上的值。 std::cout << "sizeof(std::vector) = " << sizeof(std::vector) << std::endl; - ASSERT(sizeof(vec) == ?, "Fill in the correct value."); + ASSERT(sizeof(vec) == 40, "Fill in the correct value."); { vec[20] = false; - ASSERT(?vec[20], "Fill in `vec[20]` or `!vec[20]`."); + ASSERT(!vec[20], "Fill in `vec[20]` or `!vec[20]`."); } { vec.push_back(false); - ASSERT(vec.size() == ?, "Fill in the correct value."); - ASSERT(?vec[100], "Fill in `vec[100]` or `!vec[100]`."); + ASSERT(vec.size() == 101, "Fill in the correct value."); + ASSERT(!vec[100], "Fill in `vec[100]` or `!vec[100]`."); } { auto ref = vec[30]; - ASSERT(?ref, "Fill in `ref` or `!ref`"); + ASSERT(ref, "Fill in `ref` or `!ref`"); ref = false; - ASSERT(?ref, "Fill in `ref` or `!ref`"); + ASSERT(!ref, "Fill in `ref` or `!ref`"); // THINK: WHAT and WHY? - ASSERT(?vec[30], "Fill in `vec[30]` or `!vec[30]`."); + ASSERT(!vec[30], "Fill in `vec[30]` or `!vec[30]`."); } return 0; } diff --git a/exercises/27_strides/main.cpp b/exercises/27_strides/main.cpp index baceaf2a9..9e6d7a33f 100644 --- a/exercises/27_strides/main.cpp +++ b/exercises/27_strides/main.cpp @@ -16,6 +16,12 @@ using udim = unsigned int; std::vector strides(std::vector const &shape) { std::vector strides(shape.size()); // TODO: 完成函数体，根据张量形状计算张量连续存储时的步长。 + if (shape.empty()) return strides; + udim s = 1; // stride for last dim + for (std::size_t i = shape.size(); i-- > 0;) { + strides[i] = s; // stride of dim i + s *= shape[i]; // accumulate for next dim (to the left) + } // READ: 逆向迭代器 std::vector::rbegin // 使用逆向迭代器可能可以简化代码 return strides; diff --git a/exercises/28_std_string/main.cpp b/exercises/28_std_string/main.cpp index d8b276274..5fcfdf31d 100644 --- a/exercises/28_std_string/main.cpp +++ b/exercises/28_std_string/main.cpp @@ -10,9 +10,9 @@ int main(int argc, char **argv) { auto world = "world"; // READ: `decltype` 表达式 // READ: `std::is_same_v` 元编程判别 - ASSERT((std::is_same_v), "Fill in the missing type."); - ASSERT((std::is_same_v), "Fill in the missing type."); + ASSERT((std::is_same_v), "Fill in the missing type."); + ASSERT((std::is_same_v), "Fill in the missing type."); // TODO: 将 `?` 替换为正确的字符串 - ASSERT(hello + ", " + world + '!' == "?", "Fill in the missing string."); + ASSERT(hello + ", " + world + '!' == "Hello, world!", "Fill in the missing string."); return 0; } diff --git a/exercises/29_std_map/main.cpp b/exercises/29_std_map/main.cpp index fcccca347..35e4c2dfa 100644 --- a/exercises/29_std_map/main.cpp +++ b/exercises/29_std_map/main.cpp @@ -7,11 +7,13 @@ template bool key_exists(std::map const &map, k const &key) { // TODO: 实现函数 + return map.find(key) != map.end(); } template void set(std::map &map, k key, v value) { // TODO: 实现函数 + map[std::move(key)] = std::move(value); } // ---- 不要修改以下代码 ---- diff --git a/exercises/30_std_unique_ptr/main.cpp b/exercises/30_std_unique_ptr/main.cpp index 9b98b5794..6d049c5c8 100644 --- a/exercises/30_std_unique_ptr/main.cpp +++ b/exercises/30_std_unique_ptr/main.cpp @@ -14,10 +14,13 @@ class Resource { public: void record(char record) { _records.push_back(record); + // std::cout << "ptr->_records: " << _records << std::endl; } ~Resource() { + // std::cout << "~Resource(): _records: " << _records << std::endl; RECORDS.push_back(_records); + // for (const auto& s : RECORDS) {std::cout << s << std::endl;} } }; @@ -39,13 +42,25 @@ int main(int argc, char **argv) { std::vector problems[3]; drop(forward(reset(nullptr))); + // std::cout << "After drop(forward(reset(nullptr)))" << std::endl; + // for (const auto& s : RECORDS) {std::cout << s << std::endl;} problems[0] = std::move(RECORDS); + // std::cout << "after problems[0] = std::move(RECORDS)" << std::endl; + // for (const auto& s : RECORDS) {std::cout << s << std::endl;} forward(drop(reset(forward(forward(reset(nullptr)))))); + // std::cout << "After forward(drop(reset(forward(forward(reset(nullptr))))))" << std::endl; + // for (const auto& s : RECORDS) {std::cout << s << std::endl;} problems[1] = std::move(RECORDS); + // std::cout << "After problems[1] = std::move(RECORDS);" << std::endl; + // for (const auto& s : RECORDS) {std::cout << s << std::endl;} drop(drop(reset(drop(reset(reset(nullptr)))))); + // std::cout << "After drop(drop(reset(drop(reset(reset(nullptr))))));" << std::endl; + // for (const auto& s : RECORDS) {std::cout << s << std::endl;} problems[2] = std::move(RECORDS); + // std::cout << "After problems[2] = std::move(RECORDS);" << std::endl; + // for (const auto& s : RECORDS) {std::cout << s << std::endl;} // ---- 不要修改以上代码 ---- @@ -53,15 +68,24 @@ int main(int argc, char **argv) { {"fd"}, // TODO: 分析 problems[1] 中资源的生命周期，将记录填入 `std::vector` // NOTICE: 此题结果依赖对象析构逻辑，平台相关，提交时以 CI 实际运行平台为准 - {"", "", "", "", "", "", "", ""}, - {"", "", "", "", "", "", "", ""}, + {"d", "ffr"}, + {"d", "d", "r"}, }; - // ---- 不要修改以下代码 ---- +/* +for (auto i = 0; i < 3; i++) { + for (auto j = 0; j < problems[i].size(); j++) { + std::cout << "i = " << i << ", j = " << j << ",problems[i][j].c_str = " << problems[i][j].c_str() << std::endl; + } +} +*/ + +// ---- 不要修改以下代码 ---- for (auto i = 0; i < 3; ++i) { ASSERT(problems[i].size() == answers[i].size(), "wrong size"); for (auto j = 0; j < problems[i].size(); ++j) { + // std::cout << "i = " << i << ", j = " << j << ", problems[i][j].c_str = " << problems[i][j].c_str() << ", answers[i][j] = " << answers[i][j] << std::endl; ASSERT(std::strcmp(problems[i][j].c_str(), answers[i][j]) == 0, "wrong location"); } } diff --git a/exercises/31_std_shared_ptr/main.cpp b/exercises/31_std_shared_ptr/main.cpp index febbbcc6f..8d2516bfa 100644 --- a/exercises/31_std_shared_ptr/main.cpp +++ b/exercises/31_std_shared_ptr/main.cpp @@ -10,36 +10,36 @@ int main(int argc, char **argv) { std::shared_ptr ptrs[]{shared, shared, shared}; std::weak_ptr observer = shared; - ASSERT(observer.use_count() == ?, ""); + ASSERT(observer.use_count() == 4, ""); ptrs[0].reset(); - ASSERT(observer.use_count() == ?, ""); + ASSERT(observer.use_count() == 3, ""); ptrs[1] = nullptr; - ASSERT(observer.use_count() == ?, ""); + ASSERT(observer.use_count() == 2, ""); ptrs[2] = std::make_shared(*shared); - ASSERT(observer.use_count() == ?, ""); + ASSERT(observer.use_count() == 1, ""); ptrs[0] = shared; ptrs[1] = shared; ptrs[2] = std::move(shared); - ASSERT(observer.use_count() == ?, ""); + ASSERT(observer.use_count() == 3, ""); std::ignore = std::move(ptrs[0]); ptrs[1] = std::move(ptrs[1]); ptrs[1] = std::move(ptrs[2]); - ASSERT(observer.use_count() == ?, ""); - + ASSERT(observer.use_count() == 2, ""); + shared = observer.lock(); - ASSERT(observer.use_count() == ?, ""); + ASSERT(observer.use_count() == 3, ""); shared = nullptr; for (auto &ptr : ptrs) ptr = nullptr; - ASSERT(observer.use_count() == ?, ""); + ASSERT(observer.use_count() == 0, ""); shared = observer.lock(); - ASSERT(observer.use_count() == ?, ""); + ASSERT(observer.use_count() == 0, ""); return 0; } diff --git a/exercises/32_std_transform/main.cpp b/exercises/32_std_transform/main.cpp index f4dc25a5c..124ef10cf 100644 --- a/exercises/32_std_transform/main.cpp +++ b/exercises/32_std_transform/main.cpp @@ -2,6 +2,7 @@ #include #include #include +#include // for sdtd::back_inserter (optional on many libs) // READ: `std::transform` // READ: `std::vector::begin` @@ -9,7 +10,9 @@ int main(int argc, char **argv) { std::vector val{8, 13, 21, 34, 55}; // TODO: 调用 `std::transform`，将 `v` 中的每个元素乘以 2，并转换为字符串，存入 `ans` - // std::vector ans + std::vector ans; + ans.reserve(val.size()); + std::transform(val.begin(), val.end(), std::back_inserter(ans), [](int x){ return std::to_string(x * 2); }); ASSERT(ans.size() == val.size(), "ans size should be equal to val size"); ASSERT(ans[0] == "16", "ans[0] should be 16"); ASSERT(ans[1] == "26", "ans[1] should be 26"); diff --git a/exercises/33_std_accumulate/main.cpp b/exercises/33_std_accumulate/main.cpp index 6326929d5..eda96a67e 100644 --- a/exercises/33_std_accumulate/main.cpp +++ b/exercises/33_std_accumulate/main.cpp @@ -11,7 +11,11 @@ int main(int argc, char **argv) { // - 形状为 shape； // - 连续存储； // 的张量占用的字节数 - // int size = + int size = std::accumulate( + shape, shape + 4, + static_cast(sizeof(DataType)), + [](int acc, int dim){ return acc * dim; } + ); ASSERT(size == 602112, "4x1x3x224x224 = 602112"); return 0; }