奇怪的事情

为什么用while过不了,改成for就可以了？

这是AC的代码：

/*
date : 2019-09-14 15:49:24
problem ID : 
problem WEB :
*/
#include <iostream>
#include <string.h>
#include <cstdio>
#include <queue>
#include <algorithm>
using namespace std;
#define LL long long
int n;
priority_queue<int , vector<int> > big;
priority_queue<int , vector<int> , greater<int> > small;

int main()
{
    int now;
    scanf("%d%d" , &n , &now);
    big.push(now);
    printf("%d\n" , now);
    for (int i = 2 ; i <= n ; i++)
    {
        scanf("%d" , &now);
        if (now >= big.top())
            small.push(now);
        else
            big.push(now);
        if (i % 2)
        {
            while (abs((int)big.size() - (int)small.size()) > 1)
            {
                if (big.size() > small.size())
                {
                    small.push(big.top());
                    big.pop();
                }
                else
                {
                    big.push(small.top());
                    small.pop();
                }
            }
            if (big.size() > small.size())
                printf("%d\n" , big.top());
            else
                printf("%d\n" , small.top());
        }
    }
    return 0;
}

这是0分的代码：

/*
date : 2019-09-14 15:49:24
problem ID : 
problem WEB :
*/
#include <iostream>
#include <string.h>
#include <cstdio>
#include <queue>
#include <algorithm>
using namespace std;
#define LL long long
int n;
priority_queue<int , vector<int> > big;
priority_queue<int , vector<int> , greater<int> > small;

int main()
{
    int now;
    scanf("%d%d" , &n , &now);
    big.push(now);
   n--;
    printf("%d\n" , now);
    while(n--)
    {
        scanf("%d" , &now);
        if (now >= big.top())
            small.push(now);
        else
            big.push(now);
        if (n % 2 == 0)
        {
            while (abs((int)big.size() - (int)small.size()) > 1)
            {
                if (big.size() > small.size())
                {
                    small.push(big.top());
                    big.pop();
                }
                else
                {
                    big.push(small.top());
                    small.pop();
                }
            }
            if (big.size() > small.size())
                printf("%d\n" , big.top());
            else
                printf("%d\n" , small.top());
        }
    }
    return 0;
}