title: Check Whether Arithmetic Progression Can Formed Given Array
signature: def checkWhetherArithmeticProgressionCanFormedGivenArray(arr: List[Int], n: Int) = {
source_py: def check_whether_arithmetic_progression_can_formed_given_array(arr, n):
      if (n == 1):
          return True
      arr.sort()
      d = (arr[1] - arr[0])
      for i in range(2, n):
          if ((arr[i] - arr[(i - 1)]) != d):
              return False
      return True
source_cpp: bool check_whether_arithmetic_progression_can_formed_given_array(vector<int> arr, int n) {
    if ( n == 1 ) return true;
    sort(arr.begin(), arr.end());
    int d = arr [ 1 ] - arr [ 0 ];
    for ( int i = 2;
    i < n;
    i ++ ) if ( arr [ i ] - arr [ i - 1 ] != d ) return false;
    return true;
  }