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.
Hint:
Could you do it in-place with O(1) extra space?
Could you do it in-place with O(1) extra space?
Related problem: Reverse Words in a String II
可以参考STL的rorate:
1 class Solution { 2 public: 3 void rotate(vector<int>& nums, int k) { 4 5 if(k == 0 || k > nums.size() && k % nums.size() == 0) 6 return; 7 8 k %= nums.size(); 9 10 reverse(nums.begin(), nums.end() - k); 11 reverse(nums.end() - k, nums.end()); 12 reverse(nums.begin(), nums.end()); 13 14 } 15 };