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

int main()
{
    int i, N = 1000, l = 0;
    int a[N], primeArr[l];

    printf("Array of numbers: \n");
    for (i = 0; i < N; i++)
    {
        a[i] = rand();
        printf("%d ", a[i]);
    }

    printf("\n\n");

    printf("Array of prime numbers: \n");
    for (i = 0; i < N; i++)
    {
        int k, numDivisor = 0;
        for (k = 1; k <= a[i]; k++)
            if (a[i] % k == 0)
                numDivisor++;
        if (numDivisor == 2)
        {
            primeArr[l] = a[i];
            printf("%d ", primeArr[l]);
            l++;
        }
    }

    printf("\n\n");

    if(l > 0)
    {
        printf("Max prime numbers: \n");
        int max = primeArr[0];
        for (i = 1; i < l; i++)
        {
            if (primeArr[i] >= max)
                max = primeArr[i];
        }
        printf("%d", max);
        return 0;
    }
    else
        return -1;
}