#include <stdio.h> #include <algorithm> using namespace std; int N,K,L,A[202],C[100],U[100],X; bool good(int a, int r, int l = 0) { if (X < a) X = a; if ((L - a) / 2 < r) return false; if (a == L) return true; if (a + 2 <= L && A[a]){ int u = A[a] * 10 + A[a+1]; if (u != l * 11){ int &v = U[u]; if (v < C[u]){ v++; if (good(a+2, r-1, u)) return true; v--; } } } int &v = U[A[a]]; if (v < C[A[a]]){ v++; if (good(a+1, r, A[a])) return true; v--; } return false; } int main() { #ifdef __LOCAL freopen ("input.txt","r",stdin); #endif scanf ("%d %d",&N,&K); for (int i=0;i<N;i++){ int x; scanf ("%d",&x); C[x]++; if (x < 10) A[L++] = x; else A[L++] = x / 10, A[L++] = x % 10; } sort(A,A+L); reverse(A,A+L); int rem = 0; for (int i=10;i<100;i++) rem += C[i]; do{ for (int i=0;i<100;i++) U[i] = 0; X = 0; if (good(0,rem)){ for (int i=0;i<L;i++) printf ("%d",A[i]); puts(""); if (--K == 0) break; } else{ if (X + 2 < L) sort(A+X+2,A+L); } }while(prev_permutation(A,A+L)); return 0; }