AC简捷代码给个点赞吧qwq

#include<bits/stdc++.h>
using namespace std;

const int N = 2e2+5;
int k [N],n,a,b,vis[N];

int bfs(int x)
{
	queue<pair<int,int> >q;
	q.push({x,0});
	vis[x]=1;
	while(!q.empty())
	{
		pair<int,int> cur=q.front();
		int u=cur.first,v=cur.second;
		q.pop();
		if(u==b)return v;
		if(u-k[u]>=1&&!vis[u-k[u]])
		{
			q.push({u-k[u],v+1});
			vis[u-k[u]]=1;
		}
		if(u+k[u]<=n&&!vis[u+k[u]])
		{
			q.push({u+k[u],v+1});
			vis[u+k[u]]=1;
		}
	}
	return -1;
}
int main()
{
	cin >> n >> a >> b;
	for(int i = 1;i <= n;i++)cin>>k[i];
	cout<<bfs(a);
	return 0;
}