输入输出重定向

 1 #include <stdio.h>
 2 
 3 int main(){
 4     char a[100];
 5     if(1==0){
 6         freopen("data.txt","w",stdout);
 7         printf("hello word");
 8     }else{
 9         freopen("data.txt","r",stdin);
10         
11         scanf("%s",a);
12         printf("%s\n",a);
13     }
14     
15     return 0;
16 }

data.txt
-------------------
hello word
-----------------------------

hello
请按任意键继续. . .