diff --git a/C-exp/5.4-1.cpp b/C-exp/5.4-1.cpp new file mode 100644 index 0000000..b76456c --- /dev/null +++ b/C-exp/5.4-1.cpp @@ -0,0 +1,17 @@ +#include +int main(){ + float a,b,c,m; + scanf("%f %f %f",&a,&b,&c); + m = a; + if(b>=a){ + m = b; + if(c>=b){ + m = c; + } + }else if (c>=a){ + m = c; + } + printf("%f",m); + return 0; +} + diff --git a/C-exp/5.4-2.cpp b/C-exp/5.4-2.cpp new file mode 100644 index 0000000..1d4aa24 --- /dev/null +++ b/C-exp/5.4-2.cpp @@ -0,0 +1,31 @@ +#include +#include + +int isPrimenumber(int); + +int main() { + int a, b; + printf("请输入两个正整数 a 和 b (a <= b): "); + scanf("%d %d", &a, &b); + + if (a > b || a <= 1) { + printf("%d 不是区间[1,%d]之间的有效数值\n", a, b); + return 0; + } + + if (isPrimenumber(a)) { + printf("%d 是区间[1,%d]之间的素数\n", a, b); + } else { + printf("%d 不是区间[1,%d]之间的素数\n", a, b); + } + return 0; +} + +int isPrimenumber(int a) { + for (int i = 2; i <= sqrt(a); i++) { + if (a % i == 0) { + return 0; + } + } + return 1; +} diff --git a/C-exp/5.4-3.cpp b/C-exp/5.4-3.cpp new file mode 100644 index 0000000..819e890 --- /dev/null +++ b/C-exp/5.4-3.cpp @@ -0,0 +1,29 @@ +#include + +int digit(int n, int k); + +int main() { + int n, k; + printf("分别输入整数和位数: "); + scanf("%d %d", &n, &k); + + if (k <= 0) { + printf("位数 k 必须大于 0\n"); + return 1; + } + + if (n < 0) { + n = -n; + } + + printf("整数 %d 从右边开始第 %d 位数字的值为 %d\n", n, k, digit(n, k)); + return 0; +} + +int digit(int n, int k) { + int i; + for (i = 0; i < k - 1; i++) { + n = n / 10; + } + return (n % 10); +} diff --git a/C-exp/5.4-4.cpp b/C-exp/5.4-4.cpp new file mode 100644 index 0000000..027732b --- /dev/null +++ b/C-exp/5.4-4.cpp @@ -0,0 +1,30 @@ +#include +#include + +int isPerfect(int a); + +int main() { + int i; + for (i = 1; i < 1001; i++) { + if (isPerfect(i)) { + printf("%d\n", i); + } + } + return 0; +} + +int isPerfect(int a) { + int i, sum = 1; + if (a <= 1) { + return 0; + } + for (i = 2; i <= sqrt(a); i++) { + if (a % i == 0) { + sum += i; + if (i * i != a) { + sum += a / i; + } + } + } + return sum == a; +} diff --git a/C-exp/7.3.1.cpp b/C-exp/7.3.1.cpp new file mode 100644 index 0000000..a44508e --- /dev/null +++ b/C-exp/7.3.1.cpp @@ -0,0 +1,20 @@ +#include +#include + +int main() { + float x[10], y[10], distance = 0.0; + int i, j; + for (i = 0; i < 10; i++) { + printf("请输入第%d个点的 x 坐标: ", i + 1); + scanf("%f", x + i); + printf("请输入第%d个点的 y 坐标: ", i + 1); + scanf("%f", y + i); + } + for (i = 0; i < 9; i++) { + for (j = i + 1; j < 10; j++) { // 从 i+1 开始，避免重复计算 + distance += sqrt((x[i] - x[j]) * (x[i] - x[j]) + (y[i] - y[j]) * (y[i] - y[j])); + } + } + printf("十个点的距离和为：%f\n", distance); + return 0; +} diff --git a/C-exp/7.3.3.cpp b/C-exp/7.3.3.cpp new file mode 100644 index 0000000..94b071f --- /dev/null +++ b/C-exp/7.3.3.cpp @@ -0,0 +1,31 @@ +#include +#include +#include +int compare(const void *a, const void *b) { + float fa = *(const float*)a; + float fb = *(const float*)b; + return (fa > fb) - (fa < fb); +} + +int main(){ + int n = 0; float a=0.0; + printf("请输入你需要多少个数："); + scanf("%d",&n); + while(n<1||n>20){ + printf("输入无效！请重来！"); + } + float x[n]; + for (int i = 0; i < n; i++) { + printf("请输入第%d个数: ", i + 1); + scanf("%f", &a); + x[i]=abs(a); + } + qsort(x, n, sizeof(float), compare); + + printf("排序后的数组: \n"); + for (int i = 0; i < n; i++) { + printf("%.2f ", x[i]); + } + printf("\n"); + return 0; +} diff --git a/C-exp/7.3.4.cpp b/C-exp/7.3.4.cpp new file mode 100644 index 0000000..759a69c --- /dev/null +++ b/C-exp/7.3.4.cpp @@ -0,0 +1,32 @@ +#include +int main() { + int x[5][6], i, j, min, min_row, min_column; + for (i = 0; i < 5; i++) { + printf("请输入第 %d 行的 6 个元素（空格分割）: ", i + 1); + for (j = 0; j < 6; j++) { + scanf("%d", &x[i][j]); + } + } + + for (i = 0; i < 5; i++) { + for (j = 0; j < 6; j++) { + printf("%d ", x[i][j]); + } + printf("\n"); + } + min = x[0][0]; + min_row = 0; + min_column = 0; + for (i = 0; i < 5; i++) { + for (j = 0; j < 6; j++) { + if (min >= x[i][j]) { + min = x[i][j]; + min_row = i; + min_column = j; + } + } + } + printf("最小值为：%d，在第 %d 行 第 %d 列\n", min, min_row + 1, min_column + 1); + return 0; +} + diff --git a/C-exp/7.3.5.cpp b/C-exp/7.3.5.cpp new file mode 100644 index 0000000..40666a9 --- /dev/null +++ b/C-exp/7.3.5.cpp @@ -0,0 +1,38 @@ +#include +#include +#include +int main() { + float x[5][6],max[5]; + int i=0, j=0; + for (i = 0; i < 5; i++) { + max[i] = -10000000; // 设置一个很小的初始值 + } + for (i = 0; i < 5; i++) { + printf("请输入第 %d 行的 6 个元素（空格分割）: ", (int)i + 1); + for (j = 0; j < 6; j++) { + scanf("%f", &x[(int)i][(int)j]); + if (fabs(x[(int)i][(int)j]) > max[(int)i]) { + max[(int)i] = fabs(x[(int)i][(int)j]); + } + } + } + printf("\n处理后的数组（每行元素除以其绝对值最大值）:\n"); + for (i = 0; i < 5; i++) { + for (j = 0; j < 6; j++) { + if (max[(int)i] == 0) { + printf("NaN "); + } else { + printf("%12.6f ", x[(int)i][(int)j] / max[(int)i]); + } + } + printf("\n"); + } + return 0; +} + + + + + + + diff --git a/C-exp/exp3-1.cpp b/C-exp/exp3-1.cpp new file mode 100644 index 0000000..d06f62e --- /dev/null +++ b/C-exp/exp3-1.cpp @@ -0,0 +1,25 @@ +#include +#include +int main(){ + int a,b,c,aba,abb,abc; + scanf("%d %d %d",&a,&b,&c); + aba=abs(a);abb=abs(b);abc=abs(c); + if(aba>=abb){//|a|>=|b| + if (abc>=aba){//|c|>=|a|>=|b| + printf("%d %d %d",b,a,c); + }else if(abb>=abc){//|a|>=|b|>|c| + printf("%d %d %d",c,b,a); + }else{//|a|>=|c|=>|b| + printf("%d %d %d",b,c,a); + } + }else{//|b|>=|a| + if (abc>=abb){//|c|>=|b|>=|a| + printf("%d %d %d",a,b,c); + }else if(aba>=abc){//|b|>=|a|>=|c| + printf("%d %d %d",c,a,b); + }else{//|b|>=|c|>=|a| + printf("%d %d %d",a,c,b); + } + } + return 0; +} diff --git a/C-exp/exp3-2.cpp b/C-exp/exp3-2.cpp new file mode 100644 index 0000000..8c2dc88 --- /dev/null +++ b/C-exp/exp3-2.cpp @@ -0,0 +1,22 @@ +#include +#include +int main(){ + int a,b,c; float avg,da,db,dc; + scanf("%d %d %d",&a,&b,&c); + avg = (a+b+c)/3;da=abs(a-avg);db=abs(b-avg);dc=abs(c-avg); + // da, db, dc里最小的 + if(da>=db){//da>db ，a不会是最接近的 + if(db>=dc){//da>=db>=dc + printf("%d",c); + }else{ + printf("%d",b); + } + }else{//db>da ，b不会是最接近的 + if(da>=dc){//db>=da>=dc + printf("%d",c); + }else{ + printf("%d",a); + } + } + return 0; +} diff --git a/C-exp/exp3-3.cpp b/C-exp/exp3-3.cpp new file mode 100644 index 0000000..3e440cd --- /dev/null +++ b/C-exp/exp3-3.cpp @@ -0,0 +1,7 @@ +#include +int main(){ + int a; + scanf("%d",&a); + printf("十进制为：%d，八进制为：%o，十六进制为：%x",a,a,a); + return 0; +} diff --git a/C-exp/exp4-1.c b/C-exp/exp4-1.c new file mode 100644 index 0000000..458d33d --- /dev/null +++ b/C-exp/exp4-1.c @@ -0,0 +1,17 @@ +#include + +int main() { + double max, min, result, x; + max = 0.0; + min = 0.0; + + for (x = -2; x < 2.5; x += 0.5) { + result = x * x - 3.14 * x - 6; + max = (result >= max) ? result : max; + min = (result <= min) ? result : min; + } + + printf("最大值为：%f，最小值为：%f\n", max, min); + + return 0; +} diff --git a/C-exp/exp4-2.c b/C-exp/exp4-2.c new file mode 100644 index 0000000..ff6406c --- /dev/null +++ b/C-exp/exp4-2.c @@ -0,0 +1,26 @@ +#include + +int main() { + int i, j; + + for (i = 0; i < 10; i++) { + // 第i行控制 + if (0 == i) { + printf("\t(1)\t(2)\t(3)\t(4)\t(5)\t(6)\t(7)\t(8)\t(9)\n"); + } else { + // i = 1~9 + for (j = 0; j < 10; j++) { + if (0 == j) { + printf("(%d)\t", i); + } else { + printf("%d\t", i * j); + if (9 == j) { + printf("\n"); + } + } + } + } + } + + return 0; +} diff --git "a/C-exp/\345\256\236\351\252\2144\357\274\232\345\276\252\347\216\257\347\273\223\346\236\204.docx" "b/C-exp/\345\256\236\351\252\2144\357\274\232\345\276\252\347\216\257\347\273\223\346\236\204.docx" new file mode 100644 index 0000000..6410061 Binary files /dev/null and "b/C-exp/\345\256\236\351\252\2144\357\274\232\345\276\252\347\216\257\347\273\223\346\236\204.docx" differ