#include<stdio.h>
int main()
{float n,k,count=0;
float m;
int i=1;
scanf("%f %f\n",&n,&k);
n=n-1;
while(n>0)
{n=n-i;
count++;
i=i*2;
if(i>=k)
{m=n/k;
i=m;
if((m-i)>0)
count=count+i+1;
else
count=count+i;
n=0;
}
}
i=count;
printf("%d",i);
return 0;
}