#include <iostream>
#include <cstdio>
#include <vector>
#include <string>
#include <cstring>
#include <cmath>
using namespace std;
#define INF 0x7fffffff
const int MAXN=6005;
const int MAXM=2005*2005;
struct Node
{
int from,to,next;
int cap;
} edge[MAXM];
int tol;
int dep[MAXN];
int head[MAXN];
int min_SPF[MAXN],max_SPF[MAXN];
int spf,c;
void init()
{
tol=0;
memset(head,-1,sizeof(head));
}
void addedge(int u,int v,int w)
{
edge[tol].from=u;
edge[tol].to=v;
edge[tol].cap=w;
edge[tol].next=head[u];
head[u]=tol++;
edge[tol].from=v;
edge[tol].to=u;
edge[tol].cap=0;
edge[tol].next=head[v];
head[v]=tol++;
}
int que[MAXN];
int BFS(int start,int end)
{
int front,rear;
front=rear=0;
memset(dep,-1,sizeof(dep));
que[rear++]=start;
dep[start]=0;
while(front!=rear)
{
int u=que[front++];
if(front==MAXN)front=0;
for(int i=head[u]; i!=-1; i=edge[i].next)
{
int v=edge[i].to;
if(edge[i].cap>0&&dep[v]==-1)
{
dep[v]=dep[u]+1;
que[rear++]=v;
if(rear>=MAXN)rear=0;
if(v==end)return 1;