剑指Offer20 栈的压入弹出序列是否正确

/*************************************************************************
    > File Name: 20_IsPopOrder.cpp
    > Author: Juntaran
    > Mail: JuntaranMail@gmail.com
    > Created Time: 2016年08月30日 星期二 19时53分19秒
 ************************************************************************/

#include <stdio.h>
#include <bits/stdc++.h>

using namespace std;

bool isPopOrder(int* push, int* pop, int length)
{
    if (push==NULL || pop==NULL || length<=0)
        return false;
    
    int nextPush = 0;
    int nextPop  = 0;
    
    stack<int> stackData;
    while (nextPop < length)
    {
        // 如果当前栈为空 或栈顶元素不等于要出栈的元素，压栈
        while (stackData.empty() || stackData.top()!=pop[nextPop])
        {
            if (nextPush == length)
                break;
            
            stackData.push(push[nextPush]);
            nextPush ++;
        }
        // 入栈队列结束还没找到钙元素， wrong
        if (stackData.top() != pop[nextPop])
            break;
        // 匹配到该元素，弹出，出栈指针后移一位
        stackData.pop();
        nextPop ++;
    }
    // 如果栈内已经没有元素且出栈指针已经走完，right
    if (stackData.empty() && nextPop==length)
        return true;
    
    return false;
}

int main()
{
    int push[] = {1, 2, 3, 4, 5};
//    int pop[]  = {4, 5, 3, 2, 1};
    int pop[]  = {4, 3, 5, 1, 2};
    int length = 5;
    if (isPopOrder(push, pop, length) == true)
        printf("Right\n");
    else
        printf("Wrong\n");
    
    return 0;
}