BOJ - 11060 - 점프

import sys

def solution():
    N = int(input())
    step = list(map(int, sys.stdin.readline().split(' ')))

    dp = [1000001 for _ in range(N)]
    dp[0] = 1
    for i in range(0, N):
        j = step[i]
        for j in range(i+1, i + j + 1):
            if j < N:
                dp[j] = min(dp[j], dp[i] + 1)
    
    if dp[len(dp)-1] > 1000000: print(-1)
    else : print(dp[len(dp)-1]-1)

solution()

https://www.acmicpc.net/problem/11060