#include <iostream.h>
void main()
{
long long n,k,p,s,t1,t2;
cin>>n>>k;
p=1; t1=0;
while(p<=k)
{
p*=2; t1+=1;
}
s=p; t2=t1;
while(s<n)
{
s+=k; t2+=1;
}
cout<<t2;
}

#include <iostream>
using namespace std;