pe27

#include <stdio.h>

int isPrime(int n)
{
    if (n < 2) return 0;
    int i, sqrt_n = sqrt(n);
    for (i=2; i<=sqrt_n; i++) if (n%i == 0) return 0;
    return 1;
}


int main()
{
    int a, b, n, max = 0, product;
    for (a = -999; a < 1000; a++)
    {
        for (b = -999; b < 1000; b++)
        {
            for (n=0; isPrime(n*n+a*n+b); n++);
            if (n > max) max = n, product = a*b;
        }
    }
    printf("%d\n",product);
    return 0;
}