bfs shortest path

#include <iostream>
using namespace std;

const int MAXN = 1000;
int used[MAXN+1], Q[MAXN], P[MAXN], G[MAXN][MAXN], N, b, e;

void make_empty(){
    b=0;
    e=-1;
}

void push(int x){
    Q[++e]=x;
}

int pop(){
    return Q[b++];
}

bool emptyQ(){
    return b>e;
}

void BFS(int r){
  int  x,y,i;

  for(i=1;i<=N;i++) used[i]=0;
  make_empty();
  push(r);
  used[r]=1;
  P[r]=0;

  while(!emptyQ()){
    x=pop();
    for(i=1;i<=G[x][0];i++){
      y=G[x][i];
      if(!used[y]){
        push(y);
        used[y]=1;
        P[y]=x;
        cout<< y <<" ";
      }
    }
  }
}


int main(){

    setlocale(0,"");
    int n,x,y, startV,endW, current, pathLen = 1;

     cin >> n;

        for( int i=0; i<n; i++ ){
            cin >> y >> x;
            G[x][++G[x][0]] = y;
            G[y][++G[y][0]] = x;
        }

    cin >> endW;
    cin >> startV;
    BFS(endW);
    current = startV;
    while( P[current] != endW ) {
           current = P[current];
           pathLen++;
           }

    cout << "Shortest path: " << pathLen << "\n";

    return 0;
}
/*
17
1 7
1 9
1 2
2 4
2 6
6 7
6 10
6 5
7 3
3 10
10 11
5 11
8 11
5 10
9 10
4 5
4 8
1 11
*/