leetcode 189 Rotate Array

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.

[show hint]

Related problem: Reverse Words in a String II

Credits:
Special thanks to @Freezen for adding this problem and creating all test cases.

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class Solution {
public:
	void rotate(vector<int> &nums, int k) {
		int len = nums.size();
		if(len == 0) return ;

		k = k % len;

		int temp = len-k;

		for(int i = 0, j=temp-1; i <= j; i++, j--) {
			int tmp = nums[i];
			nums[i] = nums[j];
			nums[j] = tmp;
		}

		for(int i=temp, j=len-1; i <= j; i++, j--) {
			int tmp = nums[i];
			nums[i] = nums[j];
			nums[j] = tmp;
		}


		for(int i=0, j=len-1; i <= j; i++, j--) {
			int tmp = nums[i];
			nums[i] = nums[j];
			nums[j] = tmp;
		}
	}
}