Problem
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
Explanation: 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
Explanation: 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 (Java)
class Solution {
public boolean canMakeArithmeticProgression(int[] arr) {
Arrays.sort(arr);
for (int i = 0; i < arr.length - 2; i++) {
if (arr[i + 1] - arr[i] != arr[i + 2] - arr[i + 1]) {
return false;
}
}
return true;
}
}
Explain:
nope.
Complexity:
- Time complexity : O(n).
- Space complexity : O(n).