程序代码：

#include<stdio.h>
void main()
{
int week;
printf("\nPlease input a integer(1-7):\n");
scanf("%d",&week);
switch(week)
{
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("Saterday\n");break;
                        case 7:printf("Sunday\n");break;
                        default:printf("The input is wrong!\n");
}
}