Rotate an array of n elements to the right by k steps.
For example, with n = 7 and k = 3, the array [1,2,3,4,5,6,7]
is rotated to [5,6,7,1,2,3,4]
.
Note:
Try to come up as many solutions as you can, there are at least 3 different ways to solve this problem.
This is same as Reverse Words in a String. (https://leetcode.com/problems/reverse-words-in-a-string/)
public class Solution {
public void rotate(int[] nums, int k) {
if(nums == null || nums.length == 0) return;
int len = nums.length;
k %= len;
reverse(nums, 0, len - 1);
reverse(nums, 0, k - 1);
reverse(nums, k, len - 1);
} public void reverse(int[] arr, int start, int end){
while(start < end){
int tmp = arr[start];
arr[start] = arr[end];
arr[end] = tmp;
start ++;
end --;
}
}
}