import java.util.*;
 
public class Main {
 
	public static Scanner scan = new Scanner(System.in);
	public static void main(String[] args) {
    
	      long n = scan.nextLong();
	      StringBuilder s = new StringBuilder();
	      
	      while(n > 0) 
	      {
	    	char j = (char)(n % 26 + 96);
	    	if(n%26 == 0) {
	    		j = 122;
	    		n -= 26;
	    	}
	    	s.append(j);
	        n /= 26;
	      }
	      	
	      for(int i=s.length()-1; i>=0; i--) 
	      {
	    	  System.out.print(s.charAt(i));
	      }
      
    }
} import java.util.*; util.* java public class Main {
 
	public static Scanner scan = new Scanner(System.in);
	public static void main(String[] args) {
    
	      long n = scan.nextLong();
	      StringBuilder s = new StringBuilder();
	      
	      while(n > 0) 
	      {
	    	char j = (char)(n % 26 + 96);
	    	if(n%26 == 0) {
	    		j = 122;
	    		n -= 26;
	    	}
	    	s.append(j);
	        n /= 26;
	      }
	      	
	      for(int i=s.length()-1; i>=0; i--) 
	      {
	    	  System.out.print(s.charAt(i));
	      }
      
    }
} Main public static Scanner scan = new Scanner(System.in); scan new Scanner(System.in) public static void main(String[] args) {
    
	      long n = scan.nextLong();
	      StringBuilder s = new StringBuilder();
	      
	      while(n > 0) 
	      {
	    	char j = (char)(n % 26 + 96);
	    	if(n%26 == 0) {
	    		j = 122;
	    		n -= 26;
	    	}
	    	s.append(j);
	        n /= 26;
	      }
	      	
	      for(int i=s.length()-1; i>=0; i--) 
	      {
	    	  System.out.print(s.charAt(i));
	      }
      
    } main {
    
	      long n = scan.nextLong();
	      StringBuilder s = new StringBuilder();
	      
	      while(n > 0) 
	      {
	    	char j = (char)(n % 26 + 96);
	    	if(n%26 == 0) {
	    		j = 122;
	    		n -= 26;
	    	}
	    	s.append(j);
	        n /= 26;
	      }
	      	
	      for(int i=s.length()-1; i>=0; i--) 
	      {
	    	  System.out.print(s.charAt(i));
	      }
      
    } long n = scan.nextLong(); n scan.nextLong() scan.nextLong scan StringBuilder s = new StringBuilder(); s new StringBuilder() while(n > 0) 
	      {
	    	char j = (char)(n % 26 + 96);
	    	if(n%26 == 0) {
	    		j = 122;
	    		n -= 26;
	    	}
	    	s.append(j);
	        n /= 26;
	      } n > 0 n 0 {
	    	char j = (char)(n % 26 + 96);
	    	if(n%26 == 0) {
	    		j = 122;
	    		n -= 26;
	    	}
	    	s.append(j);
	        n /= 26;
	      } char j = (char)(n % 26 + 96); j (char)(n % 26 + 96) n % 26 n 26 96 if(n%26 == 0) {
	    		j = 122;
	    		n -= 26;
	    	} n%26 == 0 n%26 n 26 0 {
	    		j = 122;
	    		n -= 26;
	    	} j = 122 j 122 n -= 26 n 26 s.append(j) s.append s j n /= 26 n 26 for(int i=s.length()-1; i>=0; i--) 
	      {
	    	  System.out.print(s.charAt(i));
	      } int i=s.length()-1; int i=s.length()-1; i s.length()-1 s.length() s.length s 1 i>=0 i 0 i-- i-- i {
	    	  System.out.print(s.charAt(i));
	      } {
	    	  System.out.print(s.charAt(i));
	      } System.out.print(s.charAt(i)) System.out.print System.out System System.out s.charAt(i) s.charAt s i String[] args args public class Main {
 
	public static Scanner scan = new Scanner(System.in);
	public static void main(String[] args) {
    
	      long n = scan.nextLong();
	      StringBuilder s = new StringBuilder();
	      
	      while(n > 0) 
	      {
	    	char j = (char)(n % 26 + 96);
	    	if(n%26 == 0) {
	    		j = 122;
	    		n -= 26;
	    	}
	    	s.append(j);
	        n /= 26;
	      }
	      	
	      for(int i=s.length()-1; i>=0; i--) 
	      {
	    	  System.out.print(s.charAt(i));
	      }
      
    }
} public class Main {
 
	public static Scanner scan = new Scanner(System.in);
	public static void main(String[] args) {
    
	      long n = scan.nextLong();
	      StringBuilder s = new StringBuilder();
	      
	      while(n > 0) 
	      {
	    	char j = (char)(n % 26 + 96);
	    	if(n%26 == 0) {
	    		j = 122;
	    		n -= 26;
	    	}
	    	s.append(j);
	        n /= 26;
	      }
	      	
	      for(int i=s.length()-1; i>=0; i--) 
	      {
	    	  System.out.print(s.charAt(i));
	      }
      
    }
} Main
import java.util.*;
 
public class Main {
 
	public static Scanner scan = new Scanner(System.in);
	public static void main(String[] args) {
    
	      long n = scan.nextLong();
	      StringBuilder s = new StringBuilder();
	      
	      while(n > 0) 
	      {
	    	char j = (char)(n % 26 + 96);
	    	if(n%26 == 0) {
	    		j = 122;
	    		n -= 26;
	    	}
	    	s.append(j);
	        n /= 26;
	      }
	      	
	      for(int i=s.length()-1; i>=0; i--) 
	      {
	    	  System.out.print(s.charAt(i));
	      }
      
    }
}