问题标题: 酷町堂：4454

 

#include <algorithm>
#include <bitset>
#include <cctype>
#include <cerrno>
#include <clocale>
#include <cmath>
#include <complex>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <ctime>
#include <deque>
#include <exception>
#include <fstream>
#include <functional>
#include <limits>
#include <list>
#include <map>
#include <iomanip>
#include <ios>
#include <iosfwd>
#include <iostream>
#include <istream>
#include <ostream>
#include <queue>
#include <set>
#include <sstream>
#include <stack>
#include <stdexcept>
#include <streambuf>
#include <string>
#include <utility>
#include <vector>
#include <cwchar>
#include <cwctype>
using namespace std;
int main()
{
    double x,y;
    cin>>x;
    if(x>5){
        y=(x+10*0.5)/10*4;
    }
    if(3<x&&x<=5){
        y=(x+10*0.5)/10*5;
    }else{
        y=(x+10*0.5)/10*6;
    }
    cout<<y;
    return 0;
}