Day 45 算法笔记之提高篇（3）9.8 哈夫曼树

1.优先队列

#include<cstdio>
#include<cmath>
#include<vector>
#include<queue>
#include<algorithm>
using namespace std;

priority_queue<long long,vector<long long>,greater<long long>> q;

int main(){
	
	int n;
	long long temp,x,y,ans=0;
	scanf("%d",&n);
	
	for(int i=0;i<n;i++){
		scanf("%lld",&temp);
		q.push(temp);
	}
	
	while(q.size()>1){
		x=q.top();
		q.pop();
		y=q.top();
		q.pop();
		q.push(x+y);
		ans+=x+y;
	}
	
	printf("%lld\n",ans);
	
	return 0;
}