package yuki_coder; import java.util.Scanner; public class No_327 { public static void main(String[] args) { Scanner sc = new Scanner(System.in); long N = sc.nextLong(); sc.close(); if(N==0){ System.out.println("A"); }else if(N < 26){ System.out.println((char)('A' + N)); }else if(N>=26){ long[] ans = new long[12]; int c = 0; long copy = N; while(copy > 26){ copy /= 26; c++; } copy = N+1; for(int i = c; i >=0; i--){ if(i!=0){ ans[i] = copy % 26; if(ans[i] == 0){ ans[i] = 26; copy -= 26; } if(i != 1){ copy /= 26; } }else if(i==0){ ans[i] = copy / 26; if(ans[i] == 0){ ans[i] = 26; } } } for(int i = 0; i <= c; i++){ ans[i] -= 1; System.out.print((char)(ans[i] + 'A')); } System.out.println(); } } }