hdoj1151

Problem : 1151 ( Air Raid )     Judge Status : Accepted
RunId : 2873274    Language : G++    Author : huwenbiao
Code Render Status : Rendered By HDOJ G++ Code Render Version 0.01 Beta
/***************************************************************\
*Author:Hu Wenbiao
*Created Time: Wed 25 Aug 2010 05:06:48 PM CST
*File Name: d.cpp
*Description:最小路径覆盖
\***************************************************************/

//*========================*Head File*========================*\\

#include<iostream>
#include<stdio.h>
#include<stdlib.h>
#include<string.h>
/*----------------------*Global Variable*----------------------*/
int
T,n,num,a,b,lx[121],ly[121];
bool
G[121][121],mark[121];
//*=======================*Main Program*=======================*//
using namespace std;

int
path(int u){
for
(int v=1;v<=n;v++){
if
(G[u][v]&&!mark[v]){
mark[v]=true;
if
(ly[v]==-1||path(ly[v])){
lx[u]=v;
ly[v]=u;
return
1;
}
}
}

return
0;
}

int
max_match(){
memset(lx,-1,sizeof(lx));
memset(ly,-1,sizeof(ly));
int
sum=0;
for
(int i=1;i<=n;i++){
if
(lx[i]==-1){
memset(mark,false,sizeof(mark));
sum+=path(i);
}
}

return
sum;
}

int
main(){
//freopen("input","r",stdin);
scanf("%d",&T);
while
(T--){
scanf("%d%d",&n,&num);
memset(G,0,sizeof(G));
while
(num--){
scanf("%d%d",&a,&b);
G[a][b]=true;
}

printf("%d\n",n-max_match());
}
}
posted @ 2010-08-25 17:22  open source  阅读(149)  评论(0编辑  收藏