hdu 2119最小点集覆盖

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;

}