# include <stdio.h>

int main(void)
{
   double Sn = 0.0000;
	int n = 0;
	int k, i;

	scanf("%d", &k);
    
    for (i=1; i<1000000; ++i)
	{
	    Sn = Sn + (1.0000 / i);
		 ++ n;
		 if (Sn > k)
		    break;	
	}
    printf("%d\n", n);
    return 0;