Contest1334/L.cpp

#include <iostream>
#include <cstring>
#include <cstdio>
#include <algorithm>
using namespace std;
const int MAXN = 110;
bool Map[MAXN][MAXN];
int link[MAXN];
bool used[MAXN];
int n,m,k;
bool dfs(int u){
    for(int i = 1; i <= m; i++){
        if(Map[u][i] && used[i] == false ){
            used[i] = true;
            if(link[i] == -1 || dfs(link[i])){
                link[i] = u;
                return true;
            }
        }
    }
    return false;
}
int hungary(){
    memset(link,-1,sizeof(link));
    int ret = 0;
    for(int i = 1; i <= n; i++){
        memset(used,0,sizeof(used));
        if(dfs(i))ret++;
    }
    return ret;
}
int main(){
    int t = 0;
    while(~scanf("%d %d %d",&n,&m,&k)){
        memset(Map,0,sizeof(Map));
        for(int i = 1; i <= k; i++){
            int x,y;
            scanf("%d %d",&x,&y);
            Map[x][y] = 1;
        }
        int ans = hungary();
        int cnt = 0;
        for(int i = 1; i <= n; i++){
            for(int j = 1; j <= m; j++){
                if(Map[i][j] == 1){
                    Map[i][j] = 0;
                    if(ans > hungary())cnt++;
                    Map[i][j] = 1;
                }
            }
        }
        printf("Board %d have %d important blanks for %d chessmen.\n",++t,cnt,ans);
   }
}