1680. Concatenation of Consecutive Binary Numbers
https://leetcode.com/problems/concatenation-of-consecutive-binary-numbers/
Python
-
直覺的寫法,但就run的過了...
-
Time: O(N) # 迴圈要從1跑到N
-
Space: O(1)
class Solution:
def concatenatedBinary(self, n: int) -> int:
mod = 10**9+7
ans = 1
for i in range(2, n+1):
bins = str(bin(i))[2:]
ans <<= len(bins)
ans += i
ans %= mod
return ans