#include <stdio.h>
#include <stdlib.h>
#include <string.h>
// ***********************
#define	lolong	long long
#define gc(c)	do{c = getchar_unlocked();}while(0)
#define pc(c)	putchar_unlocked(c)
	extern char getchar_unlocked(void);
	extern void putchar_unlocked(char c);
static char *GETWORD(char* str) {char c;char *cp;cp=&str[0];gc(c);while(c!=EOF){if((c==' ')||(c=='\n'))break;*cp++=c;gc(c);}*cp='\0';return &str[0];}
#define	str_len(a)	mystr_len_lim(a,9999)
static int mystr_len_lim(char *str,int lim){int i=0;do{if(str[i]=='\0')break;i++;}while(i<lim);return i;}
#define GETLINE(str)	do{char *p;fgets(str,sizeof(str),stdin);p=strchr(str,'\n');if(p)*p='\0';}while(0)
static int GETLINEINT(void) {char s[34];GETLINE(s);return atoi(s);}
static int GETWORDINT(void) {char s[34];GETWORD(s);return atoi(s);}
static long GETWORDLONG(void) {char s[34];GETWORD(s);return atol(s);}
static long GETLINELONG(void) {char s[34];GETLINE(s);return atol(s);}
static int max(int a,int b){if(a>b){return a;}return b;}
static int min(int a,int b){if(a<b){return a;}return b;}
#define REP(a,b) for(int a=0;a<(b);++a)
#define REP1(a,b) for(int a=1;a<=(b);++a)
const lolong MOD = 1e9 + 7;
void outl(long n) { // 整数の表示（出力）
	int i;
	char b[30];

	if (!n) pc('@');
	else {
		if (n < 0) pc('-'), n = -n;
		i = 0; while (n>0) { n--; b[i++] = n % 26 + 'A';  n = n / 26; }
		while (i--) pc(b[i]);
	}
	pc('\n');
}

// *********************
// *********************
// *********************
int main( void ) {
	int	N;
	lolong	hum,chi;
	lolong	sum;

	N = GETLINELONG();
	outl( ++N );
}