CyclicRotation Algo and Implementation in Python

A zero-indexed array A consisting of N integers is given. Rotation of the array means that each element is shifted right by one index, and the last element of the array is also moved to the first place.

For example, the rotation of array A = [3, 8, 9, 7, 6] is [6, 3, 8, 9, 7]. The goal is to rotate array A K times; that is, each element of A will be shifted to the right by K indexes.

Implementation 1: Without using any inbuilt functionality

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def solution(A, K): result = [] length = len(A) for i in range(length): result.insert((abs((i + K) % length)), A[i]) return result

Implementation 2: Using Deque data structure

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from collections import deque def solution(A, K): items = deque(A) items.rotate(K) return list(items)

Implementation 2: One Liner solution

1 2	def solution(A, K): return A[-K % len(A):] + A[:-K % len(A)]

BinaryGap Algo and implementation in Python

A binary gap within a positive integer N is any maximal sequence of consecutive zeros that is surrounded by ones at both ends in the binary representation of N.

For example, number 9 has binary representation 1001 and contains a binary gap of length 2. The number 529 has binary representation 1000010001 and contains two binary gaps: one of length 4 and one of length 3. The number 20 has binary representation 10100 and contains one binary gap of length 1. The number 15 has binary representation 1111 and has no binary gaps.

Implementation 1:

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def solution(N): bin_list = [] bin_gap = 0 pre_gap = 0 flag = False while(N > 0): if N % 2 == 0: bin_list.append(0) else: bin_list.append(1) N = N // 2 for i in bin_list: if i == 1: flag = True if (bin_gap > pre_gap): pre_gap = bin_gap bin_gap = 0 elif (i == 0 and flag is True): bin_gap += 1 else: continue return pre_gap

Implementation 2:
 

1 2	def solution(N): return len(max((bin(N)[2:]).split('1' - 1), key=len))