Write a function that check if a number is prime.

Difficulty level
This exercise is mostly suitable for students 
#include<stdio.h>
#include<conio.h>
#include<math.h>

int isPrime(int nb)
{
	int i;

	for (i = 2; i <= sqrt(nb); i++)
		if (nb%i == 0)
			return 0;
	
	return 1;
}

void main()
{
	int a;
	printf("Enter an integer: ");
	scanf("%d", &a);

 
	if (isPrime(a))
		printf("%d is prime.\n",a);
	else
		printf("%d is not prime.\n", a);
 
	getch();
}
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