LeetCode:Rotate Array

标签：leetcode

题目描述：

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].

思路分析：将数组分为左右两部分，先将左右两部分各自翻转，最后再将整个数组整体翻转，即得结果。

代码：

class Solution
{
	public:
		void swap(int * a,int * b)
		{
			int temp = *a;
			*a = *b;
			*b = temp;
		}

		void rotate(vector<int> & nums,int k)
		{
			int length = nums.size();
			int l = length - (k % length);
			int r = k % length;
			for(int i = 0,j = l - 1;i < j;i++,j--)
				swap(&nums[i],&nums[j]);
			for(int i = l,j = length - 1;i < j;i++,j--)
				swap(&nums[i],&nums[j]);
			for(int i = 0,j = length - 1;i < j;i++,j--)
				swap(&nums[i],&nums[j]);
		}
};

LeetCode:Rotate Array

标签：leetcode

原文地址：http://blog.csdn.net/yao_wust/article/details/45722589