#include<iostream>
#include<cstdio>
using namespace std;

class Test{
public:
	double omu( double n ){
		return n;
	}
};

Test test;

int main(){
	double n;
	//scanf("%lf",&n);
	cin >> n;
	printf("%.12f\n",test.omu(n) );
	return 0;
}