- Difficulty: Easy
- Tags: LeetCode, Easy, Array, Simulation, leetcode-1920, O(n), O(1), Inplace
Problem
Given a zero-based permutation nums
(0-indexed), build an array ans
of the same length where ans[i] = nums[nums[i]]
for each 0 <= i < nums.length
and return it.
A zero-based permutation nums
is an array of distinct integers from 0
to nums.length - 1
(inclusive).
Example 1:
Input: nums = [0,2,1,5,3,4] Output: [0,1,2,4,5,3] Explanation: The array ans is built as follows: ans = [nums[nums[0]], nums[nums[1]], nums[nums[2]], nums[nums[3]], nums[nums[4]], nums[nums[5]]] = [nums[0], nums[2], nums[1], nums[5], nums[3], nums[4]] = [0,1,2,4,5,3]
Example 2:
Input: nums = [5,0,1,2,3,4] Output: [4,5,0,1,2,3] Explanation: The array ans is built as follows: ans = [nums[nums[0]], nums[nums[1]], nums[nums[2]], nums[nums[3]], nums[nums[4]], nums[nums[5]]] = [nums[5], nums[0], nums[1], nums[2], nums[3], nums[4]] = [4,5,0,1,2,3]
Constraints:
1 <= nums.length <= 1000
0 <= nums[i] < nums.length
- The elements in
nums
are distinct.
Follow-up: Can you solve it without using an extra space (i.e., O(1)
memory)?