백준 14248번 : 점프 점프 (C 언어)

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

14248번: 점프 점프

Code:

#include <stdio.h>
 
int n;
int arr[100001] = { 0, };
int count = 0;
int check[100001] = { 0, };
 
void dfs(int start)
{
    if (check[start] == 0)
    {
        count++;
        check[start] = 1;
    }
    int x_p = start + arr[start];
    int x_n = start - arr[start];
    if (x_p >= 1 && x_p <= n)
    {
        dfs(x_p);
    }
    if (x_n >= 1 && x_n <= n)
    {
        dfs(x_n);
    }
}
 
int main() {
    scanf("%d", &n);
    for (int i = 1; i <= n; i++)
    {
        scanf("%d", &arr[i]);
    }
    int start = 0;
    scanf("%d", &start);
    dfs(start);
    printf("%d", count);
}