根据首字母判断星期几
#include<stdio.h>int main(void){ char letter; printf("Please input the first letter of someday\n"); while((letter=getchar())!='y') { switch(letter) { case's':printf("Please input second letter\n"); if((letter=getchar())=='a') printf("saturday\n"); else if((letter=getchar())=='u') printf("sunday\n"); else printf("data error\n"); break; case'f':printf("friday\n"); break; case'm':printf("monday\n"); break; case't':printf("please input second letter\n"); if((letter=getchar())=='u') printf("tuesday\n"); else if((letter=getchar())=='h') printf("thursday\n"); else printf("data error\n"); break; case'w':printf("wednesday\n"); break; default:printf("data error\n"); } } return 0;}