isPalindrome

main.dart

bool isPalindrome(int number) {
  // Core logic explained on an example 1234
  // 1234 == 4321
  // old    new
  // Default values
  // 1234   0
  // Loop starts:
  // 123    4 (0*10 +4)
  // 12     43 (4*10+3)
  // 1      432 (43*10 +2)
  // 0      4321 (432*10 + 1)

  int oldNumber = number;
  int newNumber = 0;

  // Convert the number to its reverse until the old number is 0
  while (oldNumber != 0) {
    newNumber = newNumber * 10 + oldNumber % 10;
    oldNumber ~/= 10;
  }
  return number == newNumber;
}

void main() => print(isPalindrome(1221));