/in/foo.cc: In function 'int main()':
/in/foo.cc:41:2: error: 'guess1' was not declared in this scope
  guess1 = decode1(a);
  ^~~~~~
/in/foo.cc:42:2: error: 'guess2' was not declared in this scope
  guess2 = decode1(b);
  ^~~~~~
/in/foo.cc:43:2: error: 'guess3' was not declared in this scope
  guess3 = decode1(c);
  ^~~~~~
/in/foo.cc:47:7: error: expected ')' before '{' token
     ) {
       ^
/in/foo.cc:50:2: error: expected ')' before 'else'
  else if (   (b == decode2(guess2) && c == decode3(guess2)
  ^~~~
/in/foo.cc:58:4: error: expected ')' before 'std'
    std::cout << guess3;
    ^~~
/in/foo.cc:58:23: error: expected ')' before ';' token
    std::cout << guess3;
                       ^