3379. Transformed Array

// Approach: For each element follow the circular pointer chain; use modular arithmetic.
// Time: O(n) Space: O(n)

public class Solution
{
    public int[] ConstructTransformedArray(int[] nums)
    {
        int n = nums.Length;
        int[] ans = new int[n];

        for (int i = 0; i < n; ++i)
            ans[i] = nums[(i + nums[i] % n + n) % n];

        return ans;
    }
}