#include<stdio.h>  
#include<stdlib.h>  
int main(void){  
   int num,i,j=0,x;  
   char s[999]; 
   char str[999];
 while(scanf("%d",&num)!=EOF){  
       while (num!=0){ 
           i=num%16;  
          switch(i){  
             case 10:  
                   s[j]='A'; 
                   break;  
             case 11:  
                    s[j]='B';  
                   break;  
             case 12:  
                   s[j]='C';  
                   break;  
             case 13:  
                    s[j]='D'; 
                   break;  
             case 14:  
                    s[j]='E'; 
                   break;    
               case 15:  
                    s[j]='F'; 
                   break;  
             default:  
                  	s[j]=i;
           }  
          num=num/16;   
          j+=1; 
       } 
       j-=1; 
      for(i=j;i>=0;i--){ 
          printf("%s",s[i]); 
              
       } 
      j=0; 
       printf("\n"); 
  }  
    return 0;   
}