HDU1507 Uncle Tom's Inherited Land*

题目是跟 zoj1516是一样的，但多了匹配后的输出

详解zoj1516可见http://www.cnblogs.com/CSU3901130321/p/4228057.html

#include <cstdio>
#include <cstring>
#include <cmath>
using namespace std;

const int maxn = 55;
int n , m , k;
int g[maxn][maxn] , cx[maxn] , cy[maxn] , visy[maxn] , nx , ny;
bool col[105][105];//判断是否为鱼塘

struct Point{
    int x , y;
    Point(int x=0 , int y=0):x(x),y(y){}
};

Point px[maxn] , py[maxn];

bool ok(Point p1 , Point p2)
{
    if((p1.x == p2.x && abs(p1.y - p2.y) == 1) || (p1.y == p2.y && abs(p1.x - p2.x) == 1))
        return true;
    return false;
}

void build_graph()
{
    memset(g , 0 , sizeof(g));
    for(int i=1 ; i<=nx ; i++){
        for(int j=1 ; j<=ny ; j++){
            if(ok(px[i] , py[j]))
                g[i][j] = 1;
        }
    }
}

int dfs(int u)
{
    for(int v = 1 ; v<=ny ; v++)
        if(g[u][v] && !visy[v]){
            visy[v] = 1;
            if(cy[v] == -1 || dfs(cy[v])){
                cx[u] = v;
                cy[v] = u;
                return 1;
            }
        }
    return 0;
}

int MaxMatch()
{
    memset(cx , -1 , sizeof(cx));
    memset(cy , -1 , sizeof(cy));
    int ans = 0;
    for(int i=1 ; i<=nx ; i++){
        if(cx[i] == -1){
            memset(visy , 0 , sizeof(visy));
            ans += dfs(i);
        }
    }
    return ans;
}

int main()
{
  //  freopen("a.in" , "r"  ,stdin);
    while(scanf("%d%d" , &n , &m) , n)
    {
        scanf("%d" , &k);
        int x , y;
        memset(col , 0 , sizeof(col));
        while(k--){
            scanf("%d%d" , &x , &y);
            col[x][y] = 1;
        }
        nx = 0 , ny = 0;
        for(int i=1 ; i<=n ; i++)
            for(int j=1 ; j<=m ; j++)
                if(!col[i][j]){
                    if((i+j)&1) py[++ny] = Point(i,j);
                    else px[++nx] = Point(i,j);
                }
        //构造二分图
        build_graph();
        printf("%d
" , MaxMatch());
        for(int i=1 ; i<=nx ; i++){
            if(cx[i] != -1)
                printf("(%d,%d)--(%d,%d)
",px[i].x , px[i].y , py[cx[i]].x , py[cx[i]].y);
        }
    }
    return 0;
}