c语言switch case语句怎么用

switch(表达式){ 
    case 常量表达式1:  语句1;
    case 常量表达式2:  语句2;
    … 
    case 常量表达式n:  语句n;
    default:  语句n+1;
}

#include <stdio.h>
int main(void){
    int a;
    printf("input integer number:    ");
    scanf("%d",&a);
    switch (a){
        case 1:printf("Monday\n");  break;
        case 2:printf("Tuesday\n");   break;
        case 3:printf("Wednesday\n");  break;
        case 4:printf("Thursday\n");  break;
        case 5:printf("Friday\n");  break;
        case 6:printf("Saturday\n");  break;
        case 7:printf("Sunday\n");  break;
        default:printf("error\n");
    }
    return 0;
}