uint16_t arr[] = {2,5,45,68,12,78,10};
void setup() {
  Serial.begin(9600);
}

void loop() {
  uint16_t x = get_avr(arr,(sizeof(arr)/sizeof(arr[0])));
  Serial.println(x);
  while(1);
}

uint16_t get_avr(uint16_t A[], uint8_t size){
  uint16_t avg = 0;
  uint16_t y = 0;
  uint8_t x = size;
  while(A[y] != NULL && x != 0){
    avg += A[y];
    y++;
    x--;
  }
  avg /= size;
  return avg;
}