首页 > 代码库 > C - Network Saboteur :不熟悉
C - Network Saboteur :不熟悉
A university network is composed of N computers. System administrators gathered information on the traffic between nodes, and carefully divided the network into two subnetworks in order to minimize traffic between parts.
A disgruntled computer science student Vasya, after being expelled from the university, decided to have his revenge. He hacked into the university network and decided to reassign computers to maximize the traffic between two subnetworks.
Unfortunately, he found that calculating such worst subdivision is one of those problems he, being a student, failed to solve. So he asks you, a more successful CS student, to help him.
The traffic data are given in the form of matrix C, where Cij is the amount of data sent between ith and jth nodes (Cij = Cji, Cii = 0). The goal is to divide the network nodes into the two disjointed subsets A and B so as to maximize the sum ∑Cij (i∈A,j∈B).
A disgruntled computer science student Vasya, after being expelled from the university, decided to have his revenge. He hacked into the university network and decided to reassign computers to maximize the traffic between two subnetworks.
Unfortunately, he found that calculating such worst subdivision is one of those problems he, being a student, failed to solve. So he asks you, a more successful CS student, to help him.
The traffic data are given in the form of matrix C, where Cij is the amount of data sent between ith and jth nodes (Cij = Cji, Cii = 0). The goal is to divide the network nodes into the two disjointed subsets A and B so as to maximize the sum ∑Cij (i∈A,j∈B).
Input
The first line of input contains a number of nodes N (2 <= N <= 20). The following N lines, containing N space-separated integers each, represent the traffic matrix C (0 <= Cij <= 10000).
Output file must contain a single integer -- the maximum traffic between the subnetworks.
Output file must contain a single integer -- the maximum traffic between the subnetworks.
Output
Output must contain a single integer -- the maximum traffic between the subnetworks.
Sample Input
3
0 50 30
50 0 40
30 40 0
Sample Output
90
题目意思:
有多个结点,每个结点之间有距离,把这些结点分成两部分,A部分结点之间认为没有距离,但与B部分每个结点都有距离,求使其最大的距离
解法:
DFS暴力枚举的方法
1 #include<iostream>
2
3 using namespace std;
4
5 const int Max = 21;
6 const bool A = true;
7 const bool B = false;
8
9 int n, map[Max][Max], ans = 0;
10 bool set[Max];
11
12 void dfs(int dep, int sum)
13 {
14 if(dep > n){
15 if(sum > ans)
16 ans = sum;
17 return;
18 }
19
20 int m;
21 m = 0;
22 set[dep] = A;
23 for(int i = 1; i <= dep; i ++)
24 if(set[i] == B)
25 m += map[i][dep];
26 dfs(dep + 1, sum + m);
27
28 m = 0;
29 set[dep] = B;
30 for(int i = 1; i <= dep; i ++)
31 if(set[i] == A)
32 m += map[i][dep];
33 dfs(dep + 1, sum + m);
34 }
35
36 int main()
37 {
38 cin >> n;
39 for(int i = 1; i <= n; i ++)
40 for(int j = 1; j <= n; j ++)
41 cin >> map[i][j];
42 dfs(1, 0);
43 cout << ans << endl;
44 return 0;
45 }
C - Network Saboteur :不熟悉
声明:以上内容来自用户投稿及互联网公开渠道收集整理发布,本网站不拥有所有权,未作人工编辑处理,也不承担相关法律责任,若内容有误或涉及侵权可进行投诉: 投诉/举报 工作人员会在5个工作日内联系你,一经查实,本站将立刻删除涉嫌侵权内容。