switch语句是C语言中的一种控制结构，用于根据表达式的值进行多路分支。switch语句的基本格式如下：switch(表达式){case 常量表达式1:语句1break;case 常量表达式2:语句2break;default:语句n+1}表达式的值与常量表达式的值进行比较，如果相等则执行对应的语句。如果没有匹配的常量表达式，则执行default后面的语句。注意，每个case后面都需要加上break语句，以避免执行下一个case中的语句 。
C语言中使用switch语句
switch语句简介
switch语句是C语言中的一种多分支选择结构，它根据表达式的值来选择执行相应的代码块，switch语句可以替代多个if-else语句，使代码更加简洁易读。
switch语句的语法
switch (expression) {
case constant1:
// 当expression等于constant1时执行的代码
break;
case constant2:
// 当expression等于constant2时执行的代码
break;
...
default:
// 当expression不等于任何case常量时执行的代码
}
switch语句的使用实例
1、判断一个整数的奇偶性
include <stdio.h>
int main() {
int num;
printf("请输入一个整数：");
scanf("%d", &num);
switch (num % 2) {
case 0:
printf("%d是偶数。
", num);
break;
case 1:
printf("%d是奇数。
", num);
break;
default:
printf("输入错误。
");
}
return 0;
}
2、根据用户输入的成绩评级
include <stdio.h>
int main() {
int score;
printf("请输入你的成绩(0-100):");
scanf("%d", &score);
switch (score / 10) {
case 10:
case 9:
printf("优秀。
");
break;
case 8:
printf("良好。
");
break;
case 7:
printf("中等。
");
break;
case 6:
printf("及格。
");
break;
default:
printf("不及格。
");
}
return 0;
}
3、实现一个简单的计算器，支持加、减、乘、除四种运算
include <stdio.h> include <stdlib.h> include <math.h> include <string.h> include <stdbool.h> include <conio.h> include <windows.h> include <time.h> include <map> include <vector> include <algorithm> include <functional> include <iomanip> include <sstream> include <iostream> include <cstring> include <queue> include <list> include <stack> include <set> include <unordered_map> include <unordered_set> include <tuple> include <bitset> include <numeric> // std::accumulate, std::inner_product, std::iota, etc.) in C++17 and later versions. If you want to use these features, you need a compiler that supports at least C++11. For example, Visual Studio Community Edition 2019 supports C++17. However, it is recommended to use the latest version of Visual Studio or other popular compilers for better compatibility and performance.
