How hard is LeetCode 360. Sort Transformed Array?

LeetCode 360. Sort Transformed Array is rated Medium on LeetCode.

What is the time complexity of LeetCode 360. Sort Transformed Array?

The Python solution on this page runs in O(n).

What is the space complexity of LeetCode 360. Sort Transformed Array?

The Python solution on this page uses O(n), where n is the length of the array \textit{nums} auxiliary space.

What topics does LeetCode 360. Sort Transformed Array cover?

LeetCode 360. Sort Transformed Array is tagged Array, Math, Two Pointers and Sorting on LeetCode.

Is LeetCode 360. Sort Transformed Array a premium problem?

Yes. LeetCode 360. Sort Transformed Array is a LeetCode Premium problem, so the full statement and test cases require a paid LeetCode subscription.

Sort Transformed Array — LeetCode 360 Python Solution

MediumLeetCode PremiumArrayMathTwo PointersSorting

Problem: #360
Pattern: Two Pointers
Reading time: 5 min
Source: leetcode.com

The problem

Given a sorted integer array nums and three integers a, b and c, apply a quadratic function of the form f(x) = ax2 + bx + c to each element nums[i] in the array, and return the array in a sorted order.

Example

Input: nums = [-4,-2,2,4], a = 1, b = 3, c = 5
Output: [3,9,15,33]

Python solution

Python

class Solution:
    def sortTransformedArray(
        self, nums: List[int], a: int, b: int, c: int
    ) -> List[int]:
        def f(x: int) -> int:
            return a * x * x + b * x + c

        n = len(nums)
        i, j = 0, n - 1
        ans = [0] * n
        for k in range(n):
            y1, y2 = f(nums[i]), f(nums[j])
            if a > 0:
                if y1 > y2:
                    ans[n - k - 1] = y1
                    i += 1
                else:
                    ans[n - k - 1] = y2
                    j -= 1
            else:
                if y1 > y2:
                    ans[k] = y2
                    j -= 1
                else:
                    ans[k] = y1
                    i += 1
        return ans

Complexity

Measure	Complexity
Time	O(n)
Space	O(n), where n is the length of the array \textit{nums} auxiliary

Pattern: Two Pointers

Use the order already in the input to discard half the search space at every step. LeetCode 360. Sort Transformed Array is filed here because LeetCode tags it Two Pointers, which is the vocabulary this hub collects.

The two pointers guide has the Python template for the pattern and the 201 LeetCode problems that use it.

Frequently asked questions

How hard is LeetCode 360. Sort Transformed Array?: LeetCode 360. Sort Transformed Array is rated Medium on LeetCode.
What is the time complexity of LeetCode 360. Sort Transformed Array?: The Python solution on this page runs in O(n).
What is the space complexity of LeetCode 360. Sort Transformed Array?: The Python solution on this page uses O(n), where n is the length of the array \textit{nums} auxiliary space.
What topics does LeetCode 360. Sort Transformed Array cover?: LeetCode 360. Sort Transformed Array is tagged Array, Math, Two Pointers and Sorting on LeetCode.
Is LeetCode 360. Sort Transformed Array a premium problem?: Yes. LeetCode 360. Sort Transformed Array is a LeetCode Premium problem, so the full statement and test cases require a paid LeetCode subscription.