🐣 문제

링크 : https://www.acmicpc.net/problem/14248

🐥 코드

/*
문제 : 점프 점프
링크 : https://www.acmicpc.net/problem/14248
*/

#include <iostream>
#include <queue>
#include <vector>
#include <algorithm>
#include <cstring>

using namespace std;

int arr[100001];
int s, N;
bool visited[100001];

void dfs(int n){
    if(n < 1 || n > N) return;
    visited[n] = true;

    dfs(n + arr[n]);
    dfs(n - arr[n]);
}

int main(){
    cin >> N;

    for(int i = 1; i <= N; i++){
        cin >> arr[i];
    }

    cin >> s;
    dfs(s);
    int ans = 0;
    for(int i = 1; i <= N; i++)
        if(visited[i]) ans++;
    
    cout << ans;
    return 0;
}