/in/foo.cc: In function 'int main()':
/in/foo.cc:21:11: error: 'fin' was not declared in this scope
     scanf(fin, "%d %d", &m, &n);
           ^~~
/in/foo.cc:43:29: error: 'fout' was not declared in this scope
             putc(pic[i][j], fout);
                             ^~~~
/in/foo.cc:45:16: error: 'fout' was not declared in this scope
         printf(fout, "\n");
                ^~~~