不说废话了，上代码。我怎么都想不明白这东西会mle.....

#include <bits/stdc++.h>
using namespace std;
int n,start1,end1,now1,step;
int a[2010],no[2010],c[2010];
bool flag = false; 
queue<int>b;
void bfs(){	
		if(b.size()>0){		
	now1 = b.front();
	c[now1]++;
	b.pop();
	if (now1-a[now1] > 0&&c[now1-a[now1]] == 0){
		b.push(now1 - a[now1]);
		if(no[now1-a[now1]] > no[now1] + 1)
			no[now1-a[now1]] = no[now1] + 1;	
	}
	if (now1+a[now1] <= n&&c[now1+a[now1]] == 0){
		b.push(now1 + a[now1]);
			if(no[now1+a[now1]] > no[now1] + 1)
				no[now1+a[now1]] = no[now1] + 1;
	}
	
	if(now1 == end1){
		printf("%d",no[end1]);
		flag = true;
		return;
	}
	bfs();
	return;
}
}
int main(){
	scanf("%d%d%d",&n,&start1,&end1);
	int i;
	for(i = 1;i <=n;i++)
		scanf("%d",&a[i]);
	for(i = 1;i <=n;i++)
		no[i] = 99999;
		no[start1] = 0;
	b.push(start1);
	if(start1 == end1||n ==0){
		printf("0");
		return 0;
	}
	if(start1 >= 1&&start1<=n&&end1>=1&&end1<=n)
		bfs();
	else{
		printf("-1");
		return 0;
	}
	if(flag == false)
	printf("-1");
	return 0;
}