#include<bits/stdc++.h>
using namespace std;
int main(){
	int N;
	cin>>N;
    if(N%10==0){
    N=N*0.8;
	cout<<N;    
	}
	else cout<<N;
}	 
  
/**************************************************************
	Problem: 1870
	User: tonghuawei
	Language: C++
	Result: Accepted
	Time:13 ms
	Memory:2072 kb
****************************************************************/