HDU1532(dinic算法最大流模板)

解题思路:裸题,但是要注意重边是叠加的。

#include<cstdio>
#include<cstring>
#include<queue>
#include<algorithm>
using namespace std;
int map[205][205],n,m;
int dis[205];
const int inf=0x3f3f3f3f;
queue<int> q;
int bfs()
{
	while(!q.empty()) q.pop();
	memset(dis,0,sizeof(dis));
	dis[1]=1;
	q.push(1);
	while(!q.empty())
	{
		int t=q.front();
		q.pop();
		for(int i=1;i<=m;i++)
		{
			if(map[t][i]&&!dis[i])
			{
				q.push(i);
				dis[i]=dis[t]+1;
				if(i==m)
				return 1;
			}
		}
	}
	return 0;
}
int dfs(int v,int cap)
{
	if(v==m) return cap;
	int tp=cap;
	for(int i=1;i<=m&&tp;i++)
	{
		if(map[v][i]&&dis[i]==dis[v]+1)
		{
			int t=dfs(i,min(tp,map[v][i]));			
			map[v][i]-=t;
			map[i][v]+=t;
			tp-=t;
		}
	}
	return cap-tp;
}
void dinic()
{
	int flow=0;
	while(bfs())
	{
		flow+=dfs(1,inf);
	}
	printf("%d\n",flow);
}
int main()
{
	int a,b,c;
	//freopen("t.txt","r",stdin);
	while(scanf("%d%d",&n,&m)!=EOF)
	{
		memset(map,0,sizeof(map));
		while(n--)
		{
			scanf("%d%d%d",&a,&b,&c);
			map[a][b]+=c;
		}
		dinic();
	}
	return 0;
}

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转载自blog.csdn.net/qq_39861441/article/details/87566503