【LeetCode】189. Rotate Array

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.

前半部分反转,后半部分反转,再整体反转。

class Solution {
public:
    void rotate(int nums[], int n, int k) {
        k %= n;
        reverse(nums, nums+(n-k));
        reverse(nums+(n-k), nums+n);
        reverse(nums, nums+n);
    }
};

时间: 2024-10-25 16:16:50

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