Leetcode 1502. Can Make Arithmetic Progression From Sequence

A sequence of numbers is called an arithmetic progression if the difference between any two consecutive elements is the same. Given an array of numbers `arr`, return `true` if the array can be rearranged to form an arithmetic progression. Otherwise, return `false`.

Programming Skills I Easy

Description

A sequence of numbers is called an arithmetic progression if the difference between any two consecutive elements is the same.

Given an array of numbers arr, return true if the array can be rearranged to form an arithmetic progression. Otherwise, return false.

Example 1:

Input: arr = [3,5,1]
Output: true

• We can reorder the elements as [1,3,5] or [5,3,1] with differences 2 and -2 respectively, between each consecutive elements.

Example 2:

Input: arr = [1,2,4]
Output: false

• There is no way to reorder the elements to obtain an arithmetic progression.

Constraints:

• 2 <= arr.length <= 1000
• -10^6 <= arr[i] <= 10^6

Solution

class Solution:
    # Iteration
    # Time Complexity: BigO(N)
    # Space Complexity: BigO(1)
    def canMakeArithmeticProgression(self, arr: List[int]) -> bool:
        arr.sort()
        diff = arr[1] - arr[0]
        for num in range(2, len(arr)):
            if (arr[num] - arr[num-1] != diff):
                return False
        return True

/**
 * Iteration
 * Time Complexity: BigO(N)
 * Space Complexity: BigO(1)
 */
function canMakeArithmeticProgression(arr: number[]): boolean {
  arr.sort((a, b) => a - b);
  const diff = arr[1] - arr[0];
  for (let i = 2; i < arr.length; i++) {
    if (arr[i] - arr[i - 1] != diff) {
      return false;
    }
  }
  return true;
}