Problem C

Given an array arr of integer values. Create the function isProgression() to check if it is possible to present the values of arr as arithmetic progression. It returns True or False. Call it for 3 arrays and print the results in the next order: arr1, arr2, arr3.

Example 1

Input: arr=[5, 7, 1, 3, -1]

Output: true. Rearrange elements like [-1, 1, 3, 5, 7] or [7, 5, 3, 1, -1].

Example 2

Input: arr=[2, 4, 16]

Output: false.