C++经典算法题-请输入星期几的第一个字母来判断一下是星期几，如果第一个字母一样， 则继续判断第二个字母。

    void main()
    {
        char letter;
        printf("please input the first letter of someday\n");
        while ((letter=getch())!='Y') /*当所按字母为Y时才结束*/
        { 
            switch (letter)
            {
                case 'S':printf("please input second letter\n");
                if((letter=getch())=='a')
                    printf("saturday\n");
                else if ((letter=getch())=='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=getch())=='u')
                        printf("tuesday\n");
                    else if ((letter=getch())=='h')
                        printf("thursday\n");
                    else printf("data error\n");
                    break;
                case 'W':printf("wednesday\n");break;
                default: printf("data error\n");
            }
        }
    }