#include<bits/stdc++.h>
using namespace std;
int main(){ 
	float n,h;
	cin>>n;
	if(n<0){
		h=0-n;
		printf("%.2f",h);
	}else{
		printf("%.2f",n);
	}
}
/**************************************************************
	Problem: 1676
	User: wangyiyang
	Language: C++
	Result: Accepted
	Time:10 ms
	Memory:2072 kb
****************************************************************/