HackerRank Matrix Layer Rotation

解答

code: python

import math

import os

import random

import re

import sys

#

# Complete the 'matrixRotation' function below.

#

# The function accepts following parameters:

# 1. 2D_INTEGER_ARRAY matrix

# 2. INTEGER r

#

def matrixRotation(matrix, r):

# Write your code here

# temporary matrix

mat = []

k = min(m,n) // 2 # compute no. of layers

# to get elements from the layer

for i in range(k):

temp = []

# a11 - a14

for j in range(i, n-1-i): # -i: to reduce layer

# a15 - a35

for j in range(i, m-1-i):

# a45 - a42

for j in range(n-1-i, i, -1):

# a41 -a21

for j in range(m-1-i, i, -1):

mat.append(temp)

# rotate elements and place it in original matrix

for i in range(k):

# find index after rotation

idx = r % len(row)

def inc():

return (idx + 1) % len(row)

for j in range(i, n-1-i): # -i: to reduce layer

idx = inc()

for j in range(i, m-1-i):

idx = inc()

for j in range(n-1-i, i, -1):

idx = inc()

for j in range(m-1-i, i, -1):

idx = inc()

# print the matrix

for row in matrix:

print(*row)

if __name__ == '__main__':

first_multiple_input = input().rstrip().split()

matrix = []

for _ in range(m):

matrix.append(list(map(int, input().rstrip().split())))

matrixRotation(matrix, r)

メモ

https://www.youtube.com/watch?v=acGcfh4JJiI