奇怪的电梯//错误代码！！！！20分

#include<iostream>
#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<cstring>
using namespace std;
int lc[100001];
int cs,begin,end,tot=-2;
void dfs(int now,int foot)
{
    if(now==end)
    {
        tot=foot;
        return;
    }
    else if(now+lc[now]<=cs)
    {
        dfs(now+lc[now],foot+1);
    }
    if(now-lc[now]>0)
    {
        dfs(now-lc[now],foot+1);
    }
    else return;
}
int main()
{ 
    cin>>cs>>begin>>end;
    for(int i=1;i<=cs;i++)
    {
        cin>>lc[i];
    }
    dfs(begin,0);
    if(tot!=-2)cout<<tot;
    else cout<<-1;
    return 0;
}