/in/foo.cc: In function 'void lev(char)':
/in/foo.cc:15:20: error: return-statement with a value, in function returning 'void' [-fpermissive]
  case '+' : return 1;break;
                    ^
/in/foo.cc:16:20: error: return-statement with a value, in function returning 'void' [-fpermissive]
  case '-' : return 1;break;
                    ^
/in/foo.cc:17:20: error: return-statement with a value, in function returning 'void' [-fpermissive]
  case '*' : return 2;break;
                    ^
/in/foo.cc:18:20: error: return-statement with a value, in function returning 'void' [-fpermissive]
  case '^' : return 3;break;
                    ^
/in/foo.cc:19:20: error: return-statement with a value, in function returning 'void' [-fpermissive]
  case '(' : return 0;break;
                    ^
/in/foo.cc: In function 'void work()':
/in/foo.cc:72:40: error: invalid operands of types 'void' and 'void' to binary 'operator<'
   else if(topsym==0 || lev(sym[topsym])<lev(a[p]))
                        ~~~~~~~~~~~~~~~~^~~~~~~~~~
/in/foo.cc:75:36: error: invalid operands of types 'void' and 'void' to binary 'operator>='
    while(topsym>0&&lev(sym[topsym])>=lev(a[p]))
                    ~~~~~~~~~~~~~~~~^~~~~~~~~~~