HDU 1045——Fire Net——————【最大匹配、构图、邻接矩阵做法】

#include<stdio.h>
#include<string.h>
#include<algorithm>
#include<iostream>
using namespace std;
int vis[110][110], G[110][110], linker[110], used[110];
char Map[110][110];
bool dfs(int u,int _n){
    for(int v = 1; v <= _n; v++){
        if(G[u][v] && !used[v]){
            used[v] = u;
            if(linker[v] == -1 || dfs(linker[v],_n)){
                linker[v] = u;
                return true;
            }
        }
    }
    return false;
}
int hungary(int un,int vn){
    int ret = 0;
    memset(linker,-1,sizeof(linker));
    for(int i = 1; i <= un; i++){
        memset(used,0,sizeof(used));
        if(dfs(i,vn))
            ret++;
    }
    return ret;
}
int main(){
    int n;
    while(scanf("%d",&n)!=EOF&&n){

        for(int i = 1; i <= n; i++){
            getchar();
            for(int j = 1; j <= n; j++){
                scanf("%c",&Map[i][j]);
            }
        }
        memset(vis,0,sizeof(vis));
        int vn = 0, flag;
        for(int i = 1; i <= n; i++){
            flag = 1;
            for(int j = 1; j <= n; j++){
                if(Map[i][j] == ‘X‘){
                    flag = 1;
                }else{
                    if(flag) {
                        vn++;
                        flag = 0;
                    }
                    vis[i][j] = vn;
                }
            }
        }
        memset(G,0,sizeof(G));
        int un = 0;
        for(int j = 1; j <= n; j++){
            flag = 1;
            for(int i = 1; i <= n; i++){
                if(Map[i][j] == ‘X‘){
                    flag = 1;
                }else{
                    if(flag){
                        un++;
                        flag = 0;
                    }
                    G[un][vis[i][j]] = 1;
                }
            }
        }
        int ans = hungary(un,vn);
        printf("%d\n",ans);
    }
    return 0;
}