#include <stdio.h> // printf
#include <stdlib.h> // rand, srand
#include <time.h> // time

int MyRand() // You may implement your own Random ;-)
{
  static int seed = 1, A = 239017, B = 17239;
  seed = A * seed + B;
  return seed >> 8;
}

int main()
{
  srand(time(NULL)); // time(NULL) = time in seconds, srand = change seed of random

  // rand() = 0..RAND_MAX = 32767
  printf("%d\n", rand() % 10); // rand() % 10 = random in [0..9]
  return 0;
}