/in/foo.cc: In function 'int main()':
/in/foo.cc:18:5: error: 'vector' was not declared in this scope
     vector<char>ve;
     ^~~~~~
/in/foo.cc:18:12: error: expected primary-expression before 'char'
     vector<char>ve;
            ^~~~
/in/foo.cc:35:14: error: 've' was not declared in this scope
         else ve.push_back(ch);
              ^~
/in/foo.cc:40:8: error: 've' was not declared in this scope
     if(ve[0]=='?'){
        ^~