how to make you own random function in c++ code example

Example 1: making random numbers in c++

/* rand example: guess the number */
#include <stdio.h>      /* printf, scanf, puts, NULL */
#include <stdlib.h>     /* srand, rand */
#include <time.h>       /* time */

int main ()
{
  int iSecret, iGuess;

  /* initialize random seed: */
  srand (time(NULL));

  /* generate secret number between 1 and 10: */
  iSecret = rand() % 10 + 1;

  do {
    printf ("Guess the number (1 to 10): ");
    scanf ("%d",&iGuess);
    if (iSecret<iGuess) puts ("The secret number is lower");
    else if (iSecret>iGuess) puts ("The secret number is higher");
  } while (iSecret!=iGuess);

  puts ("Congratulations!");
  return 0;
}

Example 2: how to make a random number in c++

#include <iostream>
#include <stdlib.h>
#include <time.h>
using namespace std;
int main() {
	srand(time(NULL)	);
	const char arrayNum[7] = {'0', '1', '2', '3', '4', '5', '6'};
	int RandIndex = rand() % 7;
	cout<<RandIndex<<endl;
	return 0;
}