#include<iostream>
#include<vector>
using namespace std;
int main(){
	vector <int> game;
    vector <int>::iterator it;
    int temp=1,n,k,result;
	cin>>n>>k;
	for(int i=1;i<n+1;++i){
		game.push_back(i);//1-n排序 
	}
	while(game.size()>1){
		for(it=game.begin();it!=game.end();++it){
			if(temp%k==0||temp%10==k){
				it=game.erase(it);//删除 
				--it; 
			}
			++temp;
		}
	}
	cout<<*(game.begin());
	return 0;
}