[Python] 2579번 계단 오르기

https://www.acmicpc.net/problem/2579

 

n = int(input())
stair = [0]  # 1-based indexing

for _ in range(n):
    stair.append(int(input()))

if n == 1:
    print(stair[1])
elif n == 2:
    print(stair[1] + stair[2])
else:
    dp = [0] * (n + 1)
    dp[1] = stair[1]
    dp[2] = stair[1] + stair[2]

    for i in range(3, n + 1):
        dp[i] = max(
            dp[i - 2] + stair[i],                  # 2칸 오르기
            dp[i - 3] + stair[i - 1] + stair[i]    # 1칸 + 1칸 오르기
        )

    print(dp[n])