From c4619fd8f86b8f4981befa54ed19b5af394781b8 Mon Sep 17 00:00:00 2001
From: pengyuzhou <760783896@qq.com>
Date: Wed, 23 Mar 2022 19:11:10 +0800
Subject: [PATCH 1/2] homework3

---
 main.cpp | 22 ++++++++++++++++++++--
 1 file changed, 20 insertions(+), 2 deletions(-)

diff --git a/main.cpp b/main.cpp
index d76cce7..73a8ce9 100644
--- a/main.cpp
+++ b/main.cpp
@@ -3,6 +3,7 @@
 #include <variant>
 
 // 请修复这个函数的定义：10 分
+template<class T>
 std::ostream &operator<<(std::ostream &os, std::vector<T> const &a) {
     os << "{";
     for (size_t i = 0; i < a.size(); i++) {
@@ -16,19 +17,35 @@ std::ostream &operator<<(std::ostream &os, std::vector<T> const &a) {
 
 // 请修复这个函数的定义：10 分
 template <class T1, class T2>
-std::vector<T0> operator+(std::vector<T1> const &a, std::vector<T2> const &b) {
+auto operator+(std::vector<T1> const &a, std::vector<T2> const &b) {
     // 请实现列表的逐元素加法！10 分
     // 例如 {1, 2} + {3, 4} = {4, 6}
+    using T0 = decltype(T1{}+T2{});
+    std::vector<T0> ret;
+    for(size_t i=0;i<std::min(a.size(),b.size());i++){
+        ret.push_back(a[i]+b[i]);
+    }
+    return ret;
 }
 
 template <class T1, class T2>
-std::variant<T1, T2> operator+(std::variant<T1, T2> const &a, std::variant<T1, T2> const &b) {
+auto operator+(std::variant<T1, T2> const &a, std::variant<T1, T2> const &b) {
     // 请实现自动匹配容器中具体类型的加法！10 分
+    std::variant<T1,T2> ret;
+    std::visit([&] (auto const &t1,auto const &t2){
+        for(size_t i=0;i<std::min(t1.size(),t2.size());i++){
+        ret.push_back(t1[i]+t2[i]);
+        }
+    },a,b);
+    return ret;
 }
 
 template <class T1, class T2>
 std::ostream &operator<<(std::ostream &os, std::variant<T1, T2> const &a) {
     // 请实现自动匹配容器中具体类型的打印！10 分
+    std::visit([&](auto const &t){
+        std::cout<<t<<std::endl;
+    },a);
 }
 
 int main() {
@@ -53,3 +70,4 @@ int main() {
 
     return 0;
 }
+

From fff7714db946e7a1e5fc9d3e91feb987d0ead195 Mon Sep 17 00:00:00 2001
From: pengyuzhou <760783896@qq.com>
Date: Thu, 31 Mar 2022 10:02:49 +0800
Subject: [PATCH 2/2] update code

---
 main.cpp | 42 ++++++++++++++++++++++--------------------
 1 file changed, 22 insertions(+), 20 deletions(-)

diff --git a/main.cpp b/main.cpp
index 73a8ce9..245bdfc 100644
--- a/main.cpp
+++ b/main.cpp
@@ -1,10 +1,10 @@
 #include <iostream>
 #include <vector>
 #include <variant>
-
+//#include <algorithm>
 // 请修复这个函数的定义：10 分
 template<class T>
-std::ostream &operator<<(std::ostream &os, std::vector<T> const &a) {
+std::ostream& operator<<(std::ostream& os, std::vector<T> const& a) {
     os << "{";
     for (size_t i = 0; i < a.size(); i++) {
         os << a[i];
@@ -17,41 +17,41 @@ std::ostream &operator<<(std::ostream &os, std::vector<T> const &a) {
 
 // 请修复这个函数的定义：10 分
 template <class T1, class T2>
-auto operator+(std::vector<T1> const &a, std::vector<T2> const &b) {
+auto operator+(std::vector<T1> const& a, std::vector<T2> const& b) {
     // 请实现列表的逐元素加法！10 分
     // 例如 {1, 2} + {3, 4} = {4, 6}
-    using T0 = decltype(T1{}+T2{});
+    using T0 = decltype(T1{} + T2{});
     std::vector<T0> ret;
-    for(size_t i=0;i<std::min(a.size(),b.size());i++){
-        ret.push_back(a[i]+b[i]);
+    for (size_t i = 0; i < std::min(a.size(), b.size()); i++) {
+        ret.push_back(a[i] + b[i]);
     }
     return ret;
 }
 
 template <class T1, class T2>
-auto operator+(std::variant<T1, T2> const &a, std::variant<T1, T2> const &b) {
+std::variant<T1, T2> operator+(std::variant<T1, T2> const& a, std::variant<T1, T2> const& b) {
     // 请实现自动匹配容器中具体类型的加法！10 分
-    std::variant<T1,T2> ret;
-    std::visit([&] (auto const &t1,auto const &t2){
-        for(size_t i=0;i<std::min(t1.size(),t2.size());i++){
-        ret.push_back(t1[i]+t2[i]);
-        }
-    },a,b);
+    std::variant<T1, T2> ret;
+    std::visit([&](auto const& t1, auto const& t2) {
+
+        ret = (t1 + t2);
+        }, a, b);
     return ret;
 }
 
 template <class T1, class T2>
-std::ostream &operator<<(std::ostream &os, std::variant<T1, T2> const &a) {
+std::ostream& operator<<(std::ostream& os, std::variant<T1, T2> const& a) {
     // 请实现自动匹配容器中具体类型的打印！10 分
-    std::visit([&](auto const &t){
-        std::cout<<t<<std::endl;
-    },a);
+    std::visit([&](auto const& t) {
+        std::cout << t << std::endl;
+        }, a);
+    return os;
 }
 
 int main() {
-    std::vector<int> a = {1, 4, 2, 8, 5, 7};
+    std::vector<int> a = { 1, 4, 2, 8, 5, 7 };
     std::cout << a << std::endl;
-    std::vector<double> b = {3.14, 2.718, 0.618};
+    std::vector<double> b = { 3.14, 2.718, 0.618 };
     std::cout << b << std::endl;
     auto c = a + b;
 
@@ -63,7 +63,9 @@ int main() {
 
     std::variant<std::vector<int>, std::vector<double>> d = c;
     std::variant<std::vector<int>, std::vector<double>> e = a;
-    d = d + c + e;
+    //std::variant<std::vector<int>, std::vector<double>> f;
+
+    d = d + std::variant<std::vector<int>, std::vector<double>>(c) + e;
 
     // 应该输出 {9.28, 17.436, 7.236}
     std::cout << d << std::endl;