/in/foo.c: In function 'prime':
/in/foo.c:7:2: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
  for(i=2;i<=sqrt(n);i++)//一改错
  ^~~
/in/foo.c:10:3: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the 'for'
   return flag;
   ^~~~~~
/in/foo.c: In function 'fun':
/in/foo.c:20:2: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
  for(i=3;i<=n;i++)
  ^~~
/in/foo.c:24:3: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the 'for'
   return k; 
   ^~~~~~
/in/foo.c: In function 'fun1':
/in/foo.c:33:2: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
  for(i=m*m;i<n*n;i++) 
  ^~~
/in/foo.c:36:3: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the 'for'
   return k; 
   ^~~~~~
/in/foo.c: At top level:
/in/foo.c:41:6: warning: return type of 'main' is not 'int' [-Wmain]
 void main() 
      ^~~~