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();
k=k%len;
if(k==0) return ;
int i=0;
int j=len-k-1;
while(i<j)
swap(nums[i++],nums[j--]);
i=len-k;
j=len-1;
while(i<j)
swap(nums[i++],nums[j--]);
i=0;
j=len-1;
while(i<j)
swap(nums[i++],nums[j--]);
return ;
}
};