[LeetCode]#1920. Build Array from Permutation
Jul 15, 2021
Environment: Python 3.8
Key technique: for
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]
Analysis:
- Use formula and[i]=nums[nums[i]]
Solution:
class Solution:
def buildArray(self, nums):
return [nums[nums[i]] for i in range(len(nums))]
Submissions: