竟然编译错了，求大佬解答

#include<bits/stdc++.h>
using namespace std;

priority_queue<int> a;
priority_queue<int,vector<int>,greater<int> > b;

int main()
{
    int n;
    int kkk;
    scanf("%d%d",&n,&kkk);
    a.push(kkk);
    cout<<kkk;
    for(int i = 1;i < n;i++)
    {
        scanf("%d",&kkk);
        if(kkk > a.top())
            b.push(kkk);
        else a.push(kkk);
        if(i % 2 == 0)
        {
            while(abs(a.size() - b.size())>1)
            {
                if(a.size()>b.size())
                {
                    b.push(a.top());
                    a.pop(); 
                }
                else
                {
                    a.push(b.top());
                    b.pop();
                }
            }
            if(a.size() > b.size())
                cout<<endl<<a.top();
            else
                cout<<endl<<b.top();
        }
    }
    return 0;
}