zoukankan      html  css  js  c++  java
  • leetcode 566. Reshape the Matrix

    In MATLAB, there is a very useful function called 'reshape', which can reshape a matrix into a new one with different size but keep its original data.

    You're given a matrix represented by a two-dimensional array, and two positive integers r and c representing the row number and column number of the wanted reshaped matrix, respectively.

    The reshaped matrix need to be filled with all the elements of the original matrix in the same row-traversing order as they were.

    If the 'reshape' operation with given parameters is possible and legal, output the new reshaped matrix; Otherwise, output the original matrix.

    Example 1:

    Input: 
    nums = 
    [[1,2],
     [3,4]]
    r = 1, c = 4
    Output: 
    [[1,2,3,4]]
    Explanation:
    The row-traversing of nums is [1,2,3,4]. The new reshaped matrix is a 1 * 4 matrix, fill it row by row by using the previous list.

    Example 2:

    Input: 
    nums = 
    [[1,2],
     [3,4]]
    r = 2, c = 4
    Output: 
    [[1,2],
     [3,4]]
    Explanation:
    There is no way to reshape a 2 * 2 matrix to a 2 * 4 matrix. So output the original matrix.

     计算数组下标是关键!

    class Solution(object):
        def matrixReshape(self, nums, r, c):
            """
            :type nums: List[List[int]]
            :type r: int
            :type c: int
            :rtype: List[List[int]]
            """
            row = len(nums)
            col = len(nums[0])
            if row*col != r*c:
                return nums
            ans = [0]*r
            for i in range(0, r):
                ans[i] = [0]*c
            for j in range(0, c*r):                   
                ans[j/c][j%c] = nums[j/col][j%col]
            return ans

     直接调用numpy的函数:

    import numpy as np
    
    class Solution(object):
        def matrixReshape(self, nums, r, c):
            try:
                return np.reshape(nums, (r, c)).tolist()
            except:
                return nums
  • 相关阅读:
    hust 1260 Dominos && hust 1516 Dominos
    poj 1149 PIGS
    hust 1230 beautiful
    poj 1469 COURSES
    hdu 3062 Party
    hust 1027 Enemy Target!
    hdu 3415 Max Sum of Max-K-sub-sequence
    简单的实现轮播代码
    window.parent与window.openner区别介绍
    plupload使用指南(转)
  • 原文地址:https://www.cnblogs.com/bonelee/p/8536500.html
Copyright © 2011-2022 走看看