Skip to content

3651. Transformed Array

Difficulty: Easy

LeetCode Problem View on GitHub


3651. Transformed Array

Easy


You are given an integer array nums that represents a circular array. Your task is to create a new array result of the same size, following these rules:

For each index i (where 0 <= i < nums.length), perform the following independent actions:

  • If nums[i] > 0: Start at index i and move nums[i] steps to the right in the circular array. Set result[i] to the value of the index where you land.
  • If nums[i] < 0: Start at index i and move abs(nums[i]) steps to the left in the circular array. Set result[i] to the value of the index where you land.
  • If nums[i] == 0: Set result[i] to nums[i].

Return the new array result.

Note: Since nums is circular, moving past the last element wraps around to the beginning, and moving before the first element wraps back to the end.

 

Example 1:

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

Output: [1,1,1,3]

Explanation:

  • For nums[0] that is equal to 3, If we move 3 steps to right, we reach nums[3]. So result[0] should be 1.
  • For nums[1] that is equal to -2, If we move 2 steps to left, we reach nums[3]. So result[1] should be 1.
  • For nums[2] that is equal to 1, If we move 1 step to right, we reach nums[3]. So result[2] should be 1.
  • For nums[3] that is equal to 1, If we move 1 step to right, we reach nums[0]. So result[3] should be 3.

Example 2:

Input: nums = [-1,4,-1]

Output: [-1,-1,4]

Explanation:

  • For nums[0] that is equal to -1, If we move 1 step to left, we reach nums[2]. So result[0] should be -1.
  • For nums[1] that is equal to 4, If we move 4 steps to right, we reach nums[2]. So result[1] should be -1.
  • For nums[2] that is equal to -1, If we move 1 step to left, we reach nums[1]. So result[2] should be 4.

 

Constraints:

  • 1 <= nums.length <= 100
  • -100 <= nums[i] <= 100

Solution

class Solution {
    public int[] constructTransformedArray(int[] nums) {
        int n = nums.length;
        int ans[] = new int[n];
        for (int i = 0; i < n; i++) {
            int ele = nums[i];
            if (ele >= 0) {
                if (i + ele < n) ans[i] = nums[i + ele];
                else ans[i] = nums[(i + ele) % n];
            }
            else {
                if (i - Math.abs(ele) >= 0) ans[i] = nums[i - Math.abs(ele)];
                else ans[i] = nums[(i - Math.abs(ele) % n + n) % n];
            }
        }
        return ans;
    }
}

Complexity Analysis

  • Time Complexity: O(?)
  • Space Complexity: O(?)

Approach

Detailed explanation of the approach will be added here