#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: linzihang
	Language: C++
	Result: Accepted
	Time:9 ms
	Memory:2072 kb
****************************************************************/