Wins the Offer (XIX): Clockwise Matrix Print

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First, the primer

This series is my brush "to prove safety Offer" brush off the cattle in question notes online, it aims to enhance the ability under its own algorithm.
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Second, the title

Enter a matrix, in order from outside to inside in a clockwise order to print out sequentially for each number, for example, if you enter the following 4 X 4 matrix: 1,234,567,891,011,121,314 15 sequentially printed out 16 digital 1,2,3,4,8,12,16,15,14,13,9,5,6,7,11,10.

1, ideas

This question first of all we must first figure out what he meant was, we can draw a map on their first know what he meant, that is, as shown clockwise print out ~

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Simulation can cube rotates counterclockwise, removing operation has been done in the first row -

E.g:

1 2 3
4 5 6
7 8 9

After the output and deletes the first line, then counterclockwise rotation, it becomes:

. 9. 6
. 5. 8
. 4. 7
continues to repeat the operation. Done, the code implements a thin ~

2, programming

python2.7

Code implementation:

# -*- coding:utf-8 -*-
class Solution:
    # matrix类型为二维列表，需要返回列表
    def printMatrix(self, matrix):
        # write code here
        result = []
        while(matrix):
            # list.pop详细介绍请看：https://www.runoob.com/python/att-list-pop.html
            result+=matrix.pop(0)
            if not matrix or not matrix[0]:
                break
            matrix = self.turn(matrix)
        return result
    def turn(self,matrix):
        num_r = len(matrix)
        num_c = len(matrix[0])
        newmat = []
        for i in range(num_c):
            newmat2 = []
            for j in range(num_r):
                newmat2.append(matrix[j][i])
            newmat.append(newmat2)
        newmat.reverse()
        return newmat

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