XidianOJ 1144 合并模板

--正文

k叉huffman

很自然想到huffman，不过果然不是简单的把k个最小的找出来就行

百度后才知道，如果这么干容易使最后的合并不足k次，所以需要添加若干个权值为0(不影响结果)的虚拟点，来进行合并

#include <iostream>
#include <cstdio>
#include <cstring>
#include <algorithm> 
#include <queue>
using namespace std;

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

int n,k;

int main(){
    while (scanf("%d %d",&n,&k) != EOF){
        int i,j;
        for (i=1;i<=n;i++){
            long long element;
            scanf("%lld",&element);
            q.push(element);
        }
        int more = 0;
        if ((n-1) % (k-1) != 0){
            more = k-1-(n-1)%(k-1);
            for (i=1;i<=more;i++){
                q.push(0);
            }
        }
        int total = n + more; 
        long long res = 0;
        while (total >= 1){
            long long sum = 0;
            for (i=1;i<=k;i++){
                sum += q.top();
                q.pop();
                total --;
                if (total == 0)
                {
                    break;
                }
            }
            res += sum;
            if (!q.empty())
            {
                q.push(sum);
                total ++;
            }
        }
        printf("%lld
",res);
    }
    
    return 0;
}