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

int main() {
	double foo;
	
	sscanf("0xd", "%lg", &foo);
	cout << foo << endl;
	
	istringstream("0xd") >> foo;
	cout << foo << endl;
	
	istringstream("0xd") >> hex >> foo;
	cout << foo << endl;
	
	istringstream("d") >> hex >> foo;
	cout << foo << endl;	
}