ABC126 C - Dice and Coin

提出

code: python

n, k = map(int, input().split())

ans = 0

for i in range(1, n+1):

score = i

coins = 0

while (score < k):

coins += 1

score *= 2

if (coins == 0):

ans += 1 / n

else:

ans += (1 / n) * pow(0.5, coins)

print(ans)