#include<bits/stdc++.h>
#define ll long long
#define N 505
using namespace std;
struct node{ll x,y,z;};
queue<node> que;
ll n,i,j,a[N][N],dis[N][N],s,t,vis[N][N];
inline void upd(ll x,ll y,ll dist){
    if(x>n||y>=2*x||y<1||x<1||!vis[x][y]) return ;
    if(dis[x][y]>dist+1){
        dis[x][y] = dist+1;
        que.push((node){x,y});
    }
}
int main(){
    memset(dis,0x3f,sizeof(dis));
	ios::sync_with_stdio(false);
    cin>>n;
    for(i=1;i<=n;i++){
        for(j=1;j<=2*i-1;j++){
            cin>>a[i][j];
            ll temp = 0;
            if(i&1) temp=4-(j-1)%4;
            else temp=(j-1)%4+1;
            if(a[i][j]==temp) vis[i][j]=1;
        }
    }
    if(a[1][1]!=4){
        cout<<-1<<endl;
        return 0;
    }
    cin>>s>>t;
    dis[1][1] = 0,que.push((node){1,1});
    while(que.size()){
        node tmp = que.front();
        que.pop();
        ll dist = dis[tmp.x][tmp.y];
        if(tmp.y%2==1) upd(tmp.x,tmp.y-1,dist),upd(tmp.x,tmp.y+1,dist),upd(tmp.x+1,tmp.y+1,dist);
        else upd(tmp.x,tmp.y-1,dist),upd(tmp.x,tmp.y+1,dist),upd(tmp.x-1,tmp.y-1,dist);
    }
    if(dis[s][t]<1e9) cout<<dis[s][t]<<endl;
    else cout<<-1<<endl;
    return 0;
}