text: #include <stdio.h>
  #include "utils.h"
  
  int sumDigits(int number) {
      if (number < 10) {
          return number;
      }
      else {
          return number % 10 + sumDigits(number / 10);
      }
  }
  
  int gcd(int a, int b) {
      int c;
  
      while (a) {
          c = a;
          a = b % a;
          b = c;
      }
  
      return b;
  }
  
  int lcm(int a, int b) {
      return a * (b / gcd(a, b));
  }
  
  // Variant 19
  int main() {
      // Task 1
      showTaskTitle();
      int firstNumber, secondNumber;
  
      printf("Enter first number value: ");
      scanf("%d", &firstNumber);
  
      printf("Enter second number value: ");
      scanf("%d", &secondNumber);
  
      printf("\nGCD: %d", gcd(firstNumber, secondNumber));
      printf("\nLCM: %d\n\n", lcm(firstNumber, secondNumber));
  
      // Task 2
      showTaskTitle();
  
      int number;
      printf("Enter a number value: ");
      scanf("%d", &number);
  
      printf("\nSum of digits: %d", sumDigits(number));
  
      return 0;
  }