#include<iostream>
using namespace std;
int main()
{
    int num;
    cin>>num;
    if(num!=1 || num!=2)
    {
        cout<<"Invalid input";
        return 0;
    }
    if(num==1)
    {
    int n;
    cin>>n;
    string result="";
    while(n>0)
    {
    n--;
    result=char('A'+(n%26))+result;
    n/=26;
}
cout<<result;
}
 else if(num==2)
 {
     float n1;
     cin>>n1;
     int intp=(int)num;
     float flop=num-intp;
     string result1="";
    while(n>0)
    {
    intp--;
    result1=char('A'+(intp%26))+result1;
    intp/=26;
 }
 cout<<result;
 if(flop>0)
 {
     cout<<".";
     flop*=1000000;
     cout<<(int)flop;
 }
 }
 
return 0;
}