hdu 2119最小点集覆盖

最新推荐文章于 2025-07-23 13:59:28 发布

转载最新推荐文章于 2025-07-23 13:59:28 发布 · 71 阅读

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原文链接：http://www.cnblogs.com/moonbay/archive/2012/08/14/2638714.html

本文介绍了一种用于解决最大匹配问题的匈牙利算法实现，该算法通过构建图并应用深度优先搜索来寻找最优解。

用匈牙利就行，比较赤裸。

/*
 * hdu2119/win.cpp
 * Created on: 2012-8-13
 * Author    : ben
 */
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <cmath>
#include <algorithm>
using namespace std;

const int MAXN = 210;
int N, M, mymatch[MAXN];
bool visited[MAXN], mymap[MAXN][MAXN];

bool buildgraph() {
    int t;
    scanf("%d", &N);
    if(N == 0) {
        return false;
    }
    scanf("%d", &M);
    memset(mymap, false, sizeof(mymap));
    for(int i = 0; i < N; i++) {
        for(int j = 0; j < M; j++) {
            scanf("%d", &t);
            if(t == 1) {
                mymap[i][j] = true;
            }
        }
    }
    return true;
}
bool dfs(int k) {
    int t;
    for (int i = 0; i < M; i++) {
        if (mymap[k][i] && !visited[i]) {
            visited[i] = true; t = mymatch[i]; mymatch[i] = k;
            if (t == -1 || dfs(t)) {
                return true;
            }
            mymatch[i] = t;
        }
    }
    return false;
}
int hungary () {
    memset(mymatch, -1, sizeof(mymatch));
    int ans = 0;
    for (int i = 0; i < N; i++) {
        memset(visited, false, sizeof(visited));
        if (dfs(i)) {
            ans++;
        }
    }
    return ans;
}

int main() {
#ifndef ONLINE_JUDGE
    freopen("data.in", "r", stdin);
#endif
    while(buildgraph()) {
        printf("%d\n", hungary());
    }
    return 0;
}

转载于:https://www.cnblogs.com/moonbay/archive/2012/08/14/2638714.html