#include<stdio.h>
void main()
{
    char day;   
    printf("please input the first letter of week.\n");
    day=getchar();
    switch(day)
    {
    case 'm':printf("monday\n");break;
    case 't':printf("please input second char\n");
        day=getchar();
            if(getchar()=='u')
            printf("tuesday\n");
         else if(getchar()=='h')
            printf("thursday\n");
            else
            printf("date error\n");
            break;
    case 'W':printf("wednesday\n");break;
    case 'S':printf("please input second char\n");
            day=getchar();
         if (getchar()=='u')
            printf("sunday\n");
         else if(getchar()=='a')
            printf("saturday\n");
            else
            printf("date error");
            break;
    case 'F':printf("friday\n");break;
    default:printf("date error\n");
    }
}
这个我输入t然后输入h就出现date error但是输入u就正常
输入s时也一样。。只有一个有用。。但是我把第二个改成day==‘h’后就能正常运行了
有谁能告诉我这是为什么吗。。谢谢了。。

#include<stdio.h>
void main()
{
    char day;   
    printf("please input the first letter of week.\n");
    day=getchar();
    switch(day)
    {
    case 'm':printf("monday\n");break;
    case 't':printf("please input second char\n");
        day=getchar();/*这个是多余的*/
            if(getchar()=='u') /*因为这里是直接把getchar()的返回值用来作条件*/
            printf("tuesday\n");
         else if(getchar()=='h')
            printf("thursday\n");
            else
            printf("date error\n");
            break;
    case 'W':printf("wednesday\n");break;
    case 'S':printf("please input second char\n");
            day=getchar();/*这里也是一样的*/
         if (getchar()=='u')
            printf("sunday\n");
         else if(getchar()=='a')
            printf("saturday\n");
            else
            printf("date error");
            break;
    case 'F':printf("friday\n");break;
    default:printf("date error\n");
    }
}

恩恩。。谢谢了。。。

楼上只是把多余的删掉就能正常运行了么？

对呀。。我把那个day=getchar()删掉就可以正常运行。。怎么啊。。还有问题？

呃。。确实不能正常运行。。还是和原来一样有一个不能运行。。但是和原来相反了
输入t然后h可以运行但是u就不行了。。这倒是是为什么啊。。希望大家帮帮我。。