Ford-furkson

int flow[205][205];
int cap[205][205];

int m,n;//m表示邊數，n表示點數，均從1開始

int ford_furkerson()
{
	int ret=0;

	bool fl[205];
	int pre[205];
	int ft[205];

	while(1)
	{
		memset(fl,0,sizeof(fl));
		memset(pre,-1,sizeof(pre));
		memset(ft,0x1f,sizeof(ft));
		queue<int>q;
		q.push(1);
		fl[1]=1;
		while(!q.empty())
		{
			int v=q.front();
			q.pop();
			for(int i=1;i<=n;i++)
			{
				if(!fl[i]&&cap[v][i]>flow[v][i])
				{
					fl[i]=1;
					pre[i]=v;
					q.push(i);
					ft[i]=(ft[v]<cap[v][i]-flow[v][i]?ft[v]:cap[v][i]-flow[v][i]);
				}
			}
		}
		if(ft[n]==0x1f1f1f1f)break;
		ret+=ft[n];
		for(int i=n;pre[i]!=-1;i=pre[i])
		{
			flow[pre[i]][i]+=ft[n];
			flow[i][pre[i]]-=ft[n];
		}
	}
	return ret;
}