#include<iostream>
using namespace std;
class Temperature{
    double celcius;
    Public:
    Temperature(double c):
    celsius(c){}
    void toFahrenheit(){
        if(celcius<0){
            cout<<"Invalid input"<<endl;
        }else{
            double fahrenheit=(celcius*9.0/5.0)+32.0;
            cout<<fahrenheit<<endl;
        }
    }
};
int main()
{
    double input;
    cin>>input;
    Temperature temp(input);
    temp.toFahrenheit();
    return 0;
}