b站笔试开发C端题解0829

两道行数加起来都没我年龄大的题，难度不多说了 bilibili笔试，哔哩哔哩笔试

T1 找bilibili型数字的个数

def DoubleNumber(self , n ):
    ans, l = 0, len(str(n))
    for i in range(1, (l+1)//2):
        ans += 10**i-10**(i-1)
    if l%2==0:
        for i in range(10**(l//2-1), int(str(n)[:l//2])+1):
            if int(str(i)*2)<=n:
                ans+=1
    return ans

T2电梯

n = int(input())
times = list(map(int, input().split()))
lifts, cur = [0, 0], 0
for time in times:
    mi = min(lifts)
    index, cur = lifts.index(mi), cur+mi
    lifts[index], lifts[1-index] = lifts[index]-mi+time,  lifts[1-index]-mi
print(cur+max(lifts))