int main()
{
    int n;
    int h;
    int m;
    scanf("%d %d %d",&n,&h,&m);
    if(m <= n * h)
    {
        if(m % h == 0)
        {
            printf("%d\n",n-m/h);
        }
        else
        {
            printf("%d\n",n-m/h-1);
        }

    }
    return 0;
}