#include<bits/stdc++.h>
using namespace std;
int main()
{
	int c=0;	
	cin>>c;
	float f=0;
	f=9/(5*1.0)*c+32;
	printf("%.2f",f);
	
	
	
	
	


	return 0;
}

/**************************************************************
	Problem: 1031
	User: 21A
	Language: C++
	Result: Accepted
	Time:8 ms
	Memory:2072 kb
****************************************************************/