Question

求高手帮我看一下这一个c语言程序，到底是哪里出错了。

#include <stdio.h>
void main()
{ float t;
printf("input data t:");
scanf("%f",&t);
switch(int(t))
{ case 6: printf("it is time to get up.\n");
case 7: printf("it is time to go to school\n");
case 8:
case 9:
case 10:
case 11:
printf("good morning.\n");
case 12:
case 13:
printf("it is noon.it is time to rest\n");
case 14:
case 15:
case 16:
case 17:
printf("good evening\n");
case 18:
case 19:
case 20:
case 21:
printf("it is time to home and have homework\n");
default:
printf("good night\n");

}
}

Answer 1

#include <stdio.h>
void main()
{ int t;
printf("input data t:");
scanf("%d",&t);
switch(int(t))
{ case 6: printf("it is time to get up.\n");break;
case 7: printf("it is time to go to school\n"); break; //跳出循环，要不他执行完这句接着执行下面其他case语句
case 8:
case 9:
case 10:
case 11:
printf("good morning.\n");break;

case 12:
case 13:
printf("it is noon.it is time to rest\n");break;
case 14:
case 15:
case 16:
case 17:
printf("good evening\n");break;
case 18:
case 19:
case 20:
case 21:
printf("it is time to home and have homework\n");break;
default:
printf("good night\n");break;

}
}

追问

运行的时候还是有错，说是调试错误。debug error

追答

你那检查你软件是不是有问题。

Answer 2

错误位置： switch(int(t))
错误原因：强制类型转换的格式应该是 (类型)(表达式)，需要将类型也用括号括起来：
switch( (int) (t) )
同时，注意在break在switch语句的中的作用与使用。

追问

运行的时候还是有错，说是调试错误。debug error

追答

如果还有错误，未必是代码的问题了，可能是你所创建的项目有其他问题。可以重新创建一个新项目，把代码复制过去，重新调试运行看看。

Answer 3

#include <stdio.h>
void main()
{
int t;
printf("input data t:");
scanf("%d",&t);
switch(t)
{ case 6: printf("it is time to get up.\n");
break;
case 7: printf("it is time to go to school\n");
break;
case 8:
case 9:
case 10:
case 11:
printf("good morning.\n");
break;
case 12:
case 13:
printf("it is noon.it is time to rest\n");
break;
case 14:
case 15:
case 16:
case 17:
printf("good evening\n");
break;
case 18:
case 19:
case 20:
case 21:
printf("it is time to home and have homework\n");
break;
default:
printf("good night\n");

}
}
switch后括号内必须为整型，你把t直接声明为整型，不要经过类型转换就不报错了

Answer 4

break加在case一行中第一个分号后。

追问

运行的时候还是有错，说是调试错误。debug error

追答

你把错误信息贴出来。

Answer 5

没有加break的话，case语句会从上到下执行下去，本程序中会把所有的printf语句执行一遍。

追问

这个break加在哪里呢，

追答

举个例子：
case 6:
printf("it is time to get up.\n");
break；
那么如果(int)t == 6 的话，那么只执行case6，其后的case语句不执行，直接跳出switch语句

追问

还是有错，

追答

类型转换格式的问题， int（t）改为（int）t