void multiBase (int N,int B)
{
    int i;
    Stack s=new Stack();
}

if (isOperator(token))

    {
        op2 = (stack.pop()).intValue();
        op1 = (stack.pop()).intValue();
        result = evalSingleOp(token.charAt(0), op1, op2);
        stack.push(new Integer(result));
        //从栈中弹出操作数2
        //从栈中弹出操作数1
        //根据运算符和两个操作数调用evalSingleOp计算result;
        //计算result入栈;

    } else
        stack.push(new Integer(Integer.parseInt(token)));
    //如果是操作数
    //操作数入栈;
}