189 旋转数组
方法一 :通过逆置实现
class Solution {
public void rotate(int[] nums, int k) {
k = k % nums.length;
reverse(nums, 0, nums.length - 1);
reverse(nums, 0, k - 1);
reverse(nums, k, nums.length - 1);
}
private void reverse(int[] nums, int start, int end) {
// nums[start..end]进行原地逆置
while (start < end) {
int temp = nums[start];
nums[start] = nums[end] ;
nums[end] = temp;
++start;
--end;
}
}
}