#include <iostream> #include <cstdio> #include <cstring> #include <cmath> #include <set> #include <vector> #include <map> #include <queue> #include <set> #include <algorithm> #include <limits.h> using namespace std; #define MAXN 10000 #define MAXM 100000 const int INF = INT_MAX; typedef long long LL; struct Edge { int from,to,ci,next; Edge(){} Edge(int _from,int _to,int _ci,int _next):from(_from),to(_to),ci(_ci),next(_next){} }e[MAXM]; int head[MAXN],tot; int dis[MAXN]; int top,sta[MAXN],cur[MAXN]; int n,m; inline void init(){ memset(head,-1,sizeof(head)); tot=0; } inline void AddEdge(int u,int v,int ci0,int ci1=0){ e[tot]=Edge(u,v,ci0,head[u]); head[u]=tot++; e[tot]=Edge(v,u,ci1,head[v]); head[v]=tot++; } inline bool bfs(int st,int et){ memset(dis,0,sizeof(dis)); dis[st]=1; queue <int> q; q.push(st); while(!q.empty()){ int now=q.front(); q.pop(); for(int i=head[now];i!=-1;i=e[i].next){ int next=e[i].to; if(e[i].ci&&!dis[next]){ dis[next]=dis[now]+1; if(next==et)return true; q.push(next); } } } return false; } LL Dinic(int st,int et){ LL ans=0; while(bfs(st,et)){ top=0; memcpy(cur,head,sizeof(head)); int u=st,i; while(1){ if(u==et){ int pos,minn=INF; for(i=0;i<top;i++) { if(minn>e[sta[i]].ci){ minn=e[sta[i]].ci; pos=i; } } for(i=0;i<top;i++){ e[sta[i]].ci-=minn; e[sta[i]^1].ci+=minn; } top=pos; u=e[sta[top]].from; ans+=minn; } for(i=cur[u];i!=-1;cur[u]=i=e[i].next) if(e[i].ci&&dis[u]+1==dis[e[i].to])break; if(cur[u]!=-1){ sta[top++]=cur[u]; u=e[cur[u]].to; } else { if(top==0)break; dis[u]=0; u=e[sta[--top]].from; } } } return ans; } int ru[MAXN],chu[MAXN]; int main() { while(~scanf("%d%d",&m,&n)){ init(); for(int i=0,x,y,vi,ci;i<m;i++){ scanf("%d%d%d",&x,&y,&ci); AddEdge(x,y,ci); ru[y]++; chu[x]++; }
printf("%I64d\n",Dinic(1,n)); } return 0; }
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