OJ_哈夫曼树

题干

C++实现

• 从小根堆的选择最小的两个
• 合并加和，然后插入回小根堆
• 然后重复上述两个步骤，直到只剩一个元素

#define _CRT_SECURE_NO_WARNINGS
#include 
#include 
#include 
using namespace std;


int main() {
	int n;
	scanf("%d", &n);
	priority_queue<int> pqueue;//存储权值相反数,以实现小根堆效果
	for (int i = 0; i < n; i++)
	{
		int leaf;
		scanf("%d", &leaf);
		pqueue.push(-1*leaf);
	}
	int wpl = 0;
	while (pqueue.size() >= 2) {
		int leaf1 = pqueue.top();
		pqueue.pop();
		int leaf2 = pqueue.top();
		pqueue.pop();
		wpl += leaf1 + leaf2;
		pqueue.push(leaf1 + leaf2);
	}
	printf("%d\n", -1 * wpl);
}