建小頂堆以及推排序

/*
    建立的是一個小頂堆
*/

# include<cstdio>
# include<iostream>
# include<algorithm>
# include<cstring>
# include<string>
# include<cmath>
# include<queue>
# include<stack>
# include<set>
# include<map>

using namespace std;

# define inf 999999999

int h[101];//用來存放堆的數組
int n;//堆的大小


void _swap ( int x,int y )
{
    int  t;
    t = h[x];
    h[x] = h[y];
    h[y] = t;
}


void siftdown( int i )
{
    int t;
    int flag = 0;//用flag來記錄是否需要繼續往下調整
    while ( i * 2 <= n && flag == 0 )
    {
        if ( h[i] > h[i*2] )
        {
            t = 2*i;
        }
        else
        {
            t = i;
        }
        if ( 2*i+1 <= n )
        {
            if ( h[t] > h[2*i+1] )
            {
                t = 2*i+1;
            }
        }

        if ( i!=t )
        {
            _swap( t,i );
            i = t;
        }
        else
            flag = 1;

    }


}

void creat()
{//從最後一個非葉節點開始，逐步向上調整
    for ( int i = n/2;i >= 1;i-- )
    {
        siftdown(i);
    }
}

int deletemax()
{
    int t;
    t = h[1];
    h[1] = h[n];
    n--;
    siftdown(1);
    return t;
}


int main(void)
{
    int num;
    cin>>num;
    for ( int i = 1;i <= num;i++ )
    {
        cin>>h[i];
    }
    n = num;
    creat();
    for ( int i = 1;i <= num;i++ )
    {
        cout<<deletemax()<<endl;
    }



	return 0;
}