/in/foo.c: In function 'main':
/in/foo.c:7:26: error: 'num' undeclared (first use in this function)
    7 |         for(int i=2;i*i<=num;i++)
      |                          ^~~
/in/foo.c:7:26: note: each undeclared identifier is reported only once for each function it appears in
/in/foo.c:10:17: error: expected expression before '}' token
   10 |                 }
      |                 ^
/in/foo.c:11:13: error: 'sum' undeclared (first use in this function)
   11 |             sum+=i;
      |             ^~~
/in/foo.c:11:18: error: 'i' undeclared (first use in this function)
   11 |             sum+=i;
      |                  ^
/in/foo.c: At top level:
/in/foo.c:16:6: error: expected identifier or '(' before '}' token
   16 |      }
      |      ^
/in/foo.c:17:6: error: expected identifier or '(' before 'if'
   17 |      if(sum==num){
      |      ^~
/in/foo.c:20:7: error: expected identifier or '(' before '}' token
   20 |       }
      |       ^
/in/foo.c:21:8: error: expected identifier or '(' before 'return'
   21 |        return 0;
      |        ^~~~~~
/in/foo.c:22:1: error: expected identifier or '(' before '}' token
   22 | }
      | ^