题解 | 不相邻取数

n = int(input())

arr = list(map(int,input().split()))
#dp[i]以i为结束的最大子数组和
dp = [0] * n
dp[0] = arr[0]
if n >1:
    dp[1] = max(arr[0],arr[1])
for i in range(2,n):
    dp[i] =max(dp[i-2]+arr[i],dp[i-1]) 
print(max(dp))