ZOJ 1654

二部圖匹配問題，思路大致就是先將空地按照行進行標號，之後再按照列標號，最後把重疊的部分連一條邊，在用匈牙利求出最大的匹配數就可以了，主要是建圖這一個步驟，圖建好了就很簡單了;以下是代碼：

話說這次的代碼是不是很優美呢。。。。。。

#include<stdio.h>
#include<algorithm>
#include<string.h>
#include<iostream>
#define MAXN 51
using namespace std;
char inputmap[MAXN][MAXN];
int grap_x[MAXN][MAXN],grap_y[MAXN][MAXN];
int match_x[MAXN*MAXN],match_y[MAXN*MAXN];
int use[MAXN*MAXN],have_path[MAXN*MAXN][MAXN*MAXN];
int n,m;
int num_x,num_y;
void init()
{
    memset(grap_x,0,sizeof(grap_x));
    memset(grap_y,0,sizeof(grap_y));
    memset(have_path,0,sizeof(have_path));
    return ;
}
void build_grap()
{
    for(int i = 0; i < m; i++)
    {
        for(int j = 0; j < n; j++)
        {
            if(grap_x[i][j] != 0 && grap_y[i][j] != 0)
            {
                have_path[grap_x[i][j]][grap_y[i][j]] = 1;
            }
        }
    }
    return ;
}
int find_path(int u)
{
    for(int v = 1; v <= num_y; v++)
    {
        if(have_path[u][v] == 1 && !use[v])
        {
            use[v] = 1;
            if(match_y[v] == -1 || find_path(match_y[v]))
            {
                match_y[v] = u;
                match_x[u] = v;
                return 1;
            }
        }
    }
    return 0;
}
int maxmatch()
{
    int res = 0;
    memset(match_x,-1,sizeof(match_x));
    memset(match_y,-1,sizeof(match_y));
    for(int i = 1; i <= num_x; i++)
    {
        if(match_x[i] == -1)
        {
            memset(use,0,sizeof(use));
            res+= find_path(i);
        }
    }
    return res;
}
int main()
{
    int t;
    int num_case=1;
    int ans,judge;
    scanf("%d", &t);
    while(t--)
    {
        scanf("%d%d", &m, &n);
        for(int i = 0; i < m; i++) scanf("%s", inputmap[i]);
        init();
        num_x=0;
        for(int i = 0; i < m; i++)
        {
            judge = 0;
            for(int j = 0; j < n; j++)
            {
                if(inputmap[i][j] == 'o')
                {
                    if(!judge) num_x++;
                    grap_x[i][j] = num_x;
                    judge = 1;
                }
                if(inputmap[i][j] == '#')
                {
                    judge = 0;
                }
             }
        }
        num_y=0;
        for(int j = 0; j < n; j++)
        {
            judge = 0;
            for(int i = 0; i < m; i++)
            {
                if(inputmap[i][j] == 'o')
                {
                    if(!judge) num_y++;
                    grap_y[i][j] = num_y;
                    judge = 1;
                }
                if(inputmap[i][j] == '#')
                {
                    judge = 0;
                }
            }
        }
        build_grap();
        ans = maxmatch();
        printf("Case :%d\n",num_case++);
        printf("%d\n",ans);
    }
    return 0;
}