题解 | 健身达人每日步数 | Python O(nlogn)

N = int(input())
if N == 0:
    print(0)
    exit()
arr = list(map(int, input().split()))

# Algo
# - Count
num2cnt = {}
for num in arr:
    cnt = num2cnt.get(num)
    if cnt: num2cnt[num] = cnt + 1
    else: num2cnt[num] = 1
# - Search
nums = list(num2cnt.keys())
nums.sort(reverse=True)
days = 0
for i in range(0, N-1):
    num = arr[i]
    num2cnt[num] -= 1
    while True:
        min_num = nums[-1]
        if num2cnt[min_num] == 0:
            nums.pop()
        else:
            break
    if num > 2 * min_num:
        days += 1

# Output
print(days)