Reshape the Matrix

标签：lis   matrix   note   data   which   its   with   integer   ssi   

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 columnnumber 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.

 1 public class Solution {
 2     public int[][] matrixReshape(int[][] nums, int r, int c) {
 3         int m = nums.length, n = nums[0].length;
 4         if (m * n != r * c) return nums;
 5         
 6         int[][] result = new int[r][c];
 7         int rc = 0, cc = 0;
 8         for (int i = 0; i < m; i ++) {
 9             for (int j = 0; j < n; j++) {
10                 result[rc][cc++] = nums[i][j];
11                 if (cc == c) {
12                     cc = 0;
13                     rc++;
14                 }
15             }
16         }
17         return result;
18     }
19 }

Reshape the Matrix

标签：lis   matrix   note   data   which   its   with   integer   ssi   

原文地址：http://www.cnblogs.com/amazingzoe/p/6830659.html