#include <iostream>
#include <queue>
using namespace std;
int main(void)
{
queue<int> q;
int n,k,i;
int move=0;
int num=1;
cin>>n>>k;
for(i=n;i>0;i--)
q.push(i);
while(q.size()>1)
{
int top=q.front();
q.pop();
if(num%k!=0)
{
move++;
q.push(num);
}
num++;
}
cout<<(q.front() - move);
return 0;
}