#include <stdio.h>
#include <string.h>
#include <ctype.h>
#include <stdlib.h>

/*
 *	Return the numeric value represented by the hex digit c.
 */
struct assoc {
  char c;
  int  v;
};

struct assoc hexval[] = {{'0',0},{'1',1},{'2',2},{'3',3},{'4',4},
			 {'5',5},{'6',6},{'7',7},{'8',8},{'9',9},
			 {'a',10},{'b',11},{'c',12},{'d',13},{'e',14},{'f',15},
			 {'A',10},{'B',11},{'C',12},{'D',13},{'E',14},{'F',15}};
int getval (char c) {
  int i;
  for (i=0; i < sizeof(hexval); i++) 
    if (hexval[i].c == c) return hexval[i].v;
  return 0;
}


int main () {
  int c;
  int val;
  while (1) {
    c = getchar();
    val = 0;
    if (c == EOF) exit(0);
    while ((c != EOF) && (c != '\n') && isalnum(c)) {
      val = val*16+getval(c);
      c = getchar();
    }
    printf("%d\n", val);
    if (c == EOF) exit(0);
  } 
  return 0;
}