int main()
{
    int n,a[1000][1000];
    int i,j;
    int f=0;
    int x1,y1,x2,y2;
    scanf("%d",&n);
    for(i=0;i<n;++i)
        for(j=0;j<n;++j)
            scanf("%d",a[i]+j);
    for(i=0;i<n;++i)
    {
        for(j=0;j<n;++j)
            if(a[i][j]==0)
            {
                x1=i;
                y1=j;
                f=1;
                break;
            }
        if(f!=0)
            break;
    }
    for(i=y1;i<n;++i)
        if((a[x1][i+1]!=0) || (i+1>=n))
        {
            y2=i;
            break;
        }
    for(i=x1;i<n;++i)
        if((a[i+1][y1]!=0) || (i+1>=n))
        {
            x2=i;
            break;
        }
    if((x2-x1<2) || (y2-y1<2))
        {
            printf("%d",0);
            return 0;
        }
    printf("%d",(x2-x1-1)*(y2-y1-1));
    return 0;
}
