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


int atalakitasEsEllenorzes(char *t1,int szamrendszer){
    char t2[160];
    int i,j;
    for(i = 0, j = 0; t1[i] != '\0'; i++, j++){
        if(t1[i] >= '0' && t1[i] <= '9'){
            t2[j] = t1[i];
            continue;
        }
        int a = t1[i] - 55;
        t2[j] = (a / 10) + '0';
        j++;
        t2[j] = (a % 10) + '0';
        
    }
    
    for(i = 0; t2[i] != '\0'; i++){
        if(!((t2[i] - '0') < szamrendszer))
            return -1;
    }
    
    return atoi(t2);
}
bool beolvasasEsHibakereses(int *mibol, int *mibe, char *tomb){
    FILE *f;
    f = fopen("be.txt","r");
    if(f == NULL)
        return false;
    if(fscanf(f,"%d %d %s\n",mibol,mibe,tomb)){
        fclose(f);
        int i;
        if(!(2 <= *mibol && *mibol <= 36 && 2 <= *mibe && *mibe <= 36)){
            return false;
        }
        for(i = 0; tomb[i] != '\0'; i++){
            if(('0' <= tomb[i] && tomb[i] <= '9') || ('A' <= tomb[i] && tomb[i] <= 'Z'))
                continue;
            return false;
        }
    }
    if(atalakitasEsEllenorzes(tomb,*mibol) == -1){
        
        return false;
    }
    return true;
}
char dec_to_hex_kiir(int _dec){
    char c;
    if(_dec < 10)
        c = _dec + '0';
    else
        c = (55 + _dec);
    return c;
}
void eredmenyToFile(char *_eredmeny){
    FILE *wr;
    wr = fopen("ki.txt","w");
    if(wr != NULL){
        fprintf(wr,"%s\n",_eredmeny);
        fclose(wr);
    }
}
void atvaltas(int _mibol, int _mibe, unsigned int _szam, char *eredmeny){
    unsigned long long int temp = _szam;
    unsigned long long int digits[16], tizes_szamrendszer = 0;
    int j, i = -1;
    while(temp){
        digits[++i] = temp % 10;
        temp /= 10;
    }
    if(_mibol != 10){
        for(j = 0; j <= i; j++){
            int szorzas = 1,k;
            for(k = 1; k <= j; k++){
                szorzas *= _mibol;
            }
            tizes_szamrendszer += digits[j] * (szorzas);
        }
    }
	else{
		tizes_szamrendszer = _szam;
	}
    for(j = 0, i = 0; j != 1; i++){
        eredmeny[i] = dec_to_hex_kiir(tizes_szamrendszer % _mibe);
        tizes_szamrendszer /= _mibe;
        if(tizes_szamrendszer == 0){
            j++;
        }
    }
    i = 0;
    j = strlen(eredmeny) - 1;
    char temp2;
    while (i < j) {
      temp2 = eredmeny[i];
      eredmeny[i] = eredmeny[j];
      eredmeny[j] = temp2;
      i++;
      j--;
   }
}

int main()
{
    char tomb[160];
    int mibol, mibe;
    unsigned long long int szam;
    char eredmeny[16] = "";
    if(!beolvasasEsHibakereses(&mibol,&mibe,tomb)){
        strcpy(eredmeny,"HIBA");
    }
    else{
        szam = atalakitasEsEllenorzes(tomb,mibol);
        atvaltas(mibol,mibe,szam,eredmeny);
    }
    eredmenyToFile(eredmeny);
    
    return 0;
}