def isOperator(c):
    if ((c == '+') or (c == '-') or (c == '*') or (c == '/') or (c == '^')):
        return True
    else:
        return False
def isOperator(c):
    if ((c == '+') or (c == '-') or (c == '*') or (c == '/') or (c == '^')):
        return True
    else:
        return False