POJ-3253 Fence Repair---Huffman贪心

题目链接:

https://vjudge.net/problem/POJ-3253

题目大意:

有一个农夫要把一个木板钜成几块给定长度的小木板,每次锯都要收取一定费用,这个费用就是当前锯的这个木版的长度

给定各个要求的小木板的长度,及小木板的个数n,求最小费用

思路:

HUffman算法

优先队列

 1 #include<iostream>
 2 #include<algorithm>
 3 #include<cstdio>
 4 #include<cstring>
 5 #include<queue>
 6 #include<vector>
 7 using namespace std;
 8 typedef long long ll;
 9 int n;
10 int main()
11 {
12     while(scanf("%d", &n) != EOF)
13     {
14         priority_queue<int, vector<int>, greater<int> >q;
15         int x;
16         for(int i = 0; i < n; i++)
17         {
18             scanf("%d", &x);
19             q.push(x);
20         }
21         ll ans = 0;
22         while(q.size() > 1)
23         {
24             int a = q.top();
25             q.pop();
26             int b = q.top();
27             q.pop();
28             q.push(a + b);
29             ans += (a + b);
30         }
31         cout<<ans<<endl;
32     }
33     return 0;
34 }

原文地址:https://www.cnblogs.com/fzl194/p/8763074.html

时间: 2024-10-14 09:20:49

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