c Random number generation function __ function

The Srand () and Rand () functions in the C standard library strlib can be used to generate random numbers, but the rand () function can only generate integers [0, Rand_max], Rand_max defined differently on different machines, On my machine is 0x7fff (i.e. 32767), and the following implements its own extensible random () function:

#include <stdio.h>
#include <stdlib.h>
#include <time.h>

//My_rand (): Return uniform Random number in [0, 1]
double My_rand () {
	//rand (): Return uniform random number in [0, Rand_max]
	return (d ouble) rand ()/Rand_max;
}

int random (int min, int max) {
	return (int) (My_rand () * (max-min) + min);
}

int main () {
	int min = 5;
	int max =;
	int i = 0;
	int n = +;

	Srand (Time (NULL));
	while (I < n) {
		int r = random (min, max);
		printf ("%d", r);

		if (R < 5 | | r >) {
			printf ("error!\n");
			break;
		}

		i++;
	}
	printf ("\ n");

	return 0;
}

Reference: Rujia "Introduction to Algorithmic Competition" section 6.2