triti2

// 45% max
#include <fstream>
#include <cstdlib>
#define ifname "triti2.in"
#define ofname "triti2.out"

using namespace std;
fstream fin, fout;
unsigned int k;
unsigned long long n, nr;
char mata[1001], chrset[] = "012";

void fuck()
{
    fout.close();
}

void init()
{
    fin.open(ifname, ios::in);
    fout.open(ofname, ios::out);
    fin >> k >> n;
    fin.close();
    atexit(fuck);
}

void brut_coaie(unsigned int poz)
{
    if (poz == k) {
        nr++;
        if (nr == n) {
            mata[poz] = '\0';
            fout << mata;
            exit(0);
        }
    } else {
        for (unsigned int i = 0; chrset[i]; i++) {
            int res = mata[poz - 1] - chrset[i];
            if (res == 1 || res == -1) {
                mata[poz] = chrset[i];
                brut_coaie(poz + 1);
            }
        }
    }
}

int main()
{
    init();
    mata[0] = '1';
    brut_coaie(1);
    mata[0] = '2';
    brut_coaie(1);
    fout << -1;
    return 0;
}