Concatenation of Array Leetcode problem

  Concatenation of Array



Given an integer array nums of length n, you want to create an array ans of length 2n where ans[i] == nums[i] and ans[i + n] == nums[i] for 0 <= i < n (0-indexed).


Specifically, ans is the concatenation of two nums arrays.


Return the array ans.


 


Example 1:


Input: nums = [1,2,1]

Output: [1,2,1,1,2,1]

Explanation: The array ans is formed as follows:

- ans = [nums[0],nums[1],nums[2],nums[0],nums[1],nums[2]]

- ans = [1,2,1,1,2,1]

Example 2:


Input: nums = [1,3,2,1]

Output: [1,3,2,1,1,3,2,1]

Explanation: The array ans is formed as follows:

- ans = [nums[0],nums[1],nums[2],nums[3],nums[0],nums[1],nums[2],nums[3]]

- ans = [1,3,2,1,1,3,2,1]




class Solution {
    public int[] getConcatenation(int[] nums) {
       
        int n=nums.length;

        int [] ans = new int [2 * n];


        for(int i=0;i<n;i++)
        {
            ans[i] = nums[i] ;
             ans[i + n] = nums[i];
        }
        return ans;
    }
}

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