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

    package LeetCode_566
    
    /**
     * 566. Reshape the Matrix
     * https://leetcode.com/problems/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.
    
    Note:
    1. The height and width of the given matrix is in range [1, 100].
    2. The given r and c are all positive.
     * */
    class Solution {
        /*
        * solution: create new array by old array, Time:O(m*n), Space:O(r*c)
        * */
        fun matrixReshape(nums: Array<IntArray>, r: Int, c: Int): Array<IntArray> {
            val m = nums.size
            val n = nums[0].size
            if (r >= m && c >= n) {
                return nums
            }
            val result = Array(r) { IntArray(c) }
            var row = 0
            var col = 0
            //reshape new array by nums, so use m,n
            for (i in 0 until m) {
                for (j in 0 until n) {
                    result[row][col] = nums[i][j]
                    col++
                    //check if need to create next row
                    if (col == c) {
                        //create next row and reset the col
                        row++
                        col = 0
                    }
                }
            }
            return result
        }
    }
  • 相关阅读:
    查找表类算法//字母异位词分组
    查找表类算法//四数相加 II
    查找表类算法//四数相加 II
    第六章 类文件结构
    第六章 类文件结构
    查找表的算法//四数之和
    查找表的算法//四数之和
    第五章 调优案例分析与实战
    第五章 调优案例分析与实战
    C++_基础4-分支语句和逻辑运算符
  • 原文地址:https://www.cnblogs.com/johnnyzhao/p/14224007.html
Copyright © 2011-2022 走看看