#include <stdio.h>
unsigned int prob(double k)
{
    unsigned int i;
    unsigned int o;
o = 1;
for (i = 1;; i++)
{
    o *= 2;
    if ((o * 2) > k) break;

}

return (o);
}
int main(void)
{
    double l;
    unsigned int h;
    scanf("%lf", &l);
        h = prob(l);
        printf("%d\n", h);
    return 0;
}