问题描述
我被指示不要使用存储阵列来完成此任务.基本上,我们必须创建一个将二维数组的内容旋转 90 度的函数.
I was instructed not to use a storage array to complete this task. Basically, we have to create a function that rotates the contents of a 2d array 90 degrees.
所以如果我从这个数组开始:
So if I start off with this array:
int[][] array = {{1,2,3}, {4,5,6}, {7,8,9}};
函数应该返回一个像这样的数组:
The function should return an array like this:
{{7,4,1}, {8,5,2}, {9,6,3}}
同样,我们不允许在函数中使用创建的数组进行存储.没有存储阵列是否也能做到这一点?
Again we are not allowed to use a created array within the function for storage. Is it even possible to accomplish this without a storage array?
推荐答案
您可以通过将上半部分与下半部分一一交换来旋转/转置数组:
You can rotate/transpose the array by swapping the upper half with the lower half one by one:
import java.util.*; import java.lang.*; import java.io.*; class Ideone { public static void main (String[] args) throws java.lang.Exception { // your code goes here int[][] array = new int[][] { new int[] { 1, 2, 3}, new int[] { 4, 5, 6}, new int[] { 7, 8, 9}, }; for (int row = 0; row < 3; row++) { for (int col = 0; col < row; col++) { int t = array[row][col]; array[row][col] = array[col][row]; array[col][row] = t; } } for (int row = 0; row < 3; row++) { System.out.println(Arrays.toString(array[row])); } } }