二分匹配_HDU_1281

#include<iostream>
#include<cstdio>
#include<cstring>
const int maxn = 105;
using namespace std;
int map[maxn][maxn],n,m,k;
int link[maxn],visr[maxn],visc[maxn];
int Find(int x)
{
for(int i = 1; i <= m; i++)
{
if(map[x][i])
{
if(!visr[x] && !visc[i])
{
visr[x] = visc[i] = 1;
if(link[i] == -1 || Find(link[i]))
{
link[i] = x;
return 1;
}
else
{
visr[x] = visc[i] = 0;
}
}
}
}
return 0;
}
int Math()
{
int cnt = 0;
memset(link,-1,sizeof(link));
for(int i = 1; i <= n; i++)
{
memset(visr,0,sizeof(visr));
memset(visc,0,sizeof(visc));
if(Find(i))
cnt++;
}
return cnt;
}
int main()
{
int u,v,num=1,cnt,imp;
while(scanf("%d%d%d",&n,&m,&k) != EOF)
{
memset(map, 0, sizeof(map));
cnt = imp = 0;
while(k--)
{
scanf("%d%d",&u,&v);
map[u][v] = 1;
}
cnt = Math();
for(int i = 1; i <= n; i++)
{
for(int j = 1; j <= m; j++)
{
if(map[i][j])
{
map[i][j] = 0;
if(Math()<cnt)
imp++;
map[i][j] = 1;
}
}
}
printf("Board %d have %d important blanks for %d chessmen.\n",num++,imp,cnt);
}
return 0;
}