请问使用switch语句该怎么做

#include<stdio.h>
int main()
{
    int x;
    scanf("%d",&x);
    switch (x%7)
    {
    case 1:printf("%d天后是星期一",x); break;
    case 2:printf("%d天后是星期二",x); break;
    case 3:printf("%d天后是星期三",x); break;
    case 4:printf("%d天后是星期四",x); break;
    case 5:printf("%d天后是星期五",x); break;
    case 6:printf("%d天后是星期六",x); break;
    default:printf("%d天后是星期天",x);
    }
    return 0;
}

#include "stdio.h"
void main()
{
    int n,day;
    char week[7][20]={
        "星期天",
        "星期一",
        "星期二",
        "星期三",
        "星期四",
        "星期五",
        "星期六"        
    };
    scanf("%d",&n);
    
    day = n%7;
    
    printf("%d天后是星期%s",n,week[day]);
}