Squares

#include <stdio.h>

int PrintBoxes(int N)
{
    if (1 <= N && N < 25)
    {
        int size = N*2+1;
        for (int i = 0; i < size; i++)
        {
            for (int j = 0; j < size; j++)
            {
                if ((i == 0 || j == 0 || i == size-1 || j == size-1 ) || ((i % 2 == 0 || j % 2 == 0) && i == j) || ((i % 2 == 0) && j<i) || ((j % 2 == 0) && i<j))
                    printf("*");
                else
                    printf(" ");
            }
            printf("\n");
        }
    }
    else
    {
        printf ("Incorrect input.");
    }

}

int main()
{
    printf("\n");
    PrintBoxes(3);
    printf("\n");
    return 0;
}