#include <string>
using namespace std;
#include<algorithm>
string toHexString(int n);
//该函数可以将10进制转换为任意的radix进制数,n是要转换的十进制数
string intToA(int n,int radix)
{
string ans="";
do{
int t=n%radix;
if(t>=0&&t<=9)ans+=t+'0';
else ans+=t-10+'A';
n/=radix;
}while(n);
reverse(ans.begin(),ans.end());
return ans;
}
int main() {
int n;
cin >> n;
string hexStr = toHexString(n);
cout << hexStr << endl;
return 0;
}
string toHexString(int n) {
// write your code here......
return intToA(n,16);
}