zoukankan      html  css  js  c++  java
  • 二分图的最大团

    In a kindergarten, there are a lot of kids. All girls of the kids know each other and all boys also know each other. In addition to that, some girls and boys know each other. Now the teachers want to pick some kids to play a game, which need that all players know each other. You are to help to find maximum number of kids the teacher can pick.

    Input

    The input consists of multiple test cases. Each test case starts with a line containing three integers
    G, B (1 ≤ G, B ≤ 200) and M (0 ≤ MG × B), which is the number of girls, the number of boys and
    the number of pairs of girl and boy who know each other, respectively.
    Each of the following M lines contains two integers X and Y (1 ≤ X≤ G,1 ≤ Y ≤ B), which indicates that girl X and boy Y know each other.
    The girls are numbered from 1 to G and the boys are numbered from 1 to B.

    The last test case is followed by a line containing three zeros.

    Output

    For each test case, print a line containing the test case number( beginning with 1) followed by a integer which is the maximum number of kids the teacher can pick.

    Sample Input
    2 3 3
    1 1
    1 2
    2 3
    2 3 5
    1 1
    1 2
    2 1
    2 2
    2 3
    0 0 0
    Sample Output
    Case 1: 3
    Case 2: 4

    题意 : 所有的男生都认识,所有的女生都认识,让你寻找一个最大的一个团,使得其中的所有人之间彼此都认识
    思路分析 : 题目是让寻找一个二分图的最大团,最大团 = 补图的最大独立集 = 顶点数 - 补图的最小顶点覆盖数 = 顶点数 - 补图的二分图匹配数
    代码示例 :
    #define ll long long
    const int maxn = 1e6+5;
    const double pi = acos(-1.0);
    const int inf = 0x3f3f3f3f;
    
    bool edge[205][205];
    int girl, boy, m;
    bool used[205];
    int pt[205];
    
    bool dfs(int x){
        for(int i = 1; i <= boy; i++){
            if (edge[x][i] && !used[i]) { 
                used[i] = true;
                if (!pt[i] || dfs(pt[i])){
                    pt[i] = x;
                    return true; 
                }
            }
        }
        return false;
    }
    
    int main() {
        //freopen("in.txt", "r", stdin);
        //freopen("out.txt", "w", stdout);
        int a, b;
        int kase = 1;
        while(scanf("%d%d%d", &girl, &boy, &m) && girl+boy+m){
            memset(edge, true, sizeof(edge));
            for(int i = 1; i <= m; i++){
                scanf("%d%d", &a, &b);
                edge[a][b] = false;
            }
            int cnt = 0;
            memset(pt, 0, sizeof(pt));
            for(int i = 1; i <= girl; i++){
                memset(used, false, sizeof(used));
                if (dfs(i)) cnt++;
            }
            printf("Case %d: %d
    ", kase++, girl+boy-cnt);
        }    
        return 0;
    }
    
    东北日出西边雨 道是无情却有情
  • 相关阅读:
    Jupyter notebook 读取文件的问题
    机器学习-数据清洗和特征选择
    机器学习-逻辑回归
    Java教程
    13.并发编程
    redis 实现
    CyclicBarrier介绍
    Future模式衍生出来的更高级的应用
    并发编程 futuretask
    整理POST请求方式
  • 原文地址:https://www.cnblogs.com/ccut-ry/p/8511536.html
Copyright © 2011-2022 走看看