/in/foo.cc: In function 'int main()':
/in/foo.cc:9:18: error: 'itoa' was not declared in this scope
  itoa (j, str, 10);
                  ^
/in/foo.cc:10:12: warning: comparison with string literal results in unspecified behavior [-Waddress]
  if(str == "X"){
            ^~~