leetcode 189 Rotate Array

最新推荐文章于 2025-01-20 18:26:54 发布

最新推荐文章于 2025-01-20 18:26:54 发布 · 259 阅读

Leetcode 专栏收录该内容

127 篇文章

订阅专栏

本文介绍了一种将数组元素向右旋转k步的算法实现，并通过C++代码示例展示了具体的步骤。该方法首先反转整个数组，然后分别反转前k个元素和剩余的元素，最终达到旋转的效果。

摘要生成于 C知道，由 DeepSeek-R1 满血版支持，前往体验 >

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.

Subscribe to see which companies asked this question

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;
		}
	}
}