The maximum flow dicnic - hdu1532 template title

#include<bits/stdc++.h>
using namespace std;
#define maxn 1005
#define ll long long

const ll inf = 0x3f3f3f3f3f3f3f3f;
 
struct Edge{ll to,nxt,w;}e[maxn<<1];
int head[maxn],tot,n,m;
void init(){
    memset(e,0,sizeof e);
    memset(head,-1,sizeof head);
    tot=0;
}
void add(ll u,ll v,ll w){
    e[tot].toV =; E [TOT] .nxt head = [U]; E [TOT] .W = W; head [U] = TOT ++ ; 
} 

int D [MAXN];
 BOOL BFS () { // on residual network FIG layered configuration 
    Memset (D, 0 , the sizeof D); 
    
    Queue < int > Q;
     the while (q.size ()) q.pop (); 
    q.push ( . 1 ); D [ . 1 ] = . 1 ; 
    
    the while ( q.size ()) {
         int X = q.front (); q.pop ();
         for ( int I = head [X]; I = -! . 1 ; I = E [I] .nxt) {
             int Y =e[i].to;
            if(d[y] || e[i].w==0)continue;
            q.push(y);
            d[y]=d[x]+1;
            if(y==n)return 1;
        }
    }
    return 0;
}
int dinic(int x,ll flow){
    if (x==n)return flow;
    ll rest=flow;
    for(int i=head[x];i!=-1 && rest>0;i=e[i].nxt){
        int y=e[i].to;
        if(e[i].w==0 || d[y]!=d[x]+1)continue;
        ll k=dinic(y,min(rest,e[i].w));
        if(!k)    d[y]=0;    //y点已经被增广完毕
        e[i].w-=k; e[i^1].w+=k;
        rest-=k;
    }
    return flow-rest;
} 


int main(){
    while(cin>>m>>n){
        init();
        for(int i=1;i<=m;i++){
            ll u,v,w;
            cin>>u>>v>>w;
            add(u,v,w);
            add(v,u,0);
        }
        ll flow=0,ans=0;
        while(bfs())
            while(flow=dinic(1,inf))
                ans+=flow;
        cout<<ans<<'\n';        
    }
}