#include <bits/stdc++.h>
#define MP make_pair
#define PB push_back
#define int long long
#define FOR(i, a, b) for(int i =(a); i <=(b); ++i)
#define RE(i, n) FOR(i, 1, n)
#define FORD(i, a, b) for(int i = (a); i >= (b); --i)
#define REP(i, n) for(int i = 0;i <(n); ++i)
#define VAR(v, i) __typeof(i) v=(i)
#define FORE(i, c) for(VAR(i, (c).begin()); i != (c).end(); ++i)
#define ALL(x) (x).begin(), (x).end()
#define SZ(x) ((int)(x).size())
#ifdef LOCAL
#define debug(x) {cerr <<#x <<" = " <<x <<"\n"; }
#define debug2(x, y) {cerr <<#x <<" = " <<x <<", "<<#y <<" = " <<y <<"\n";}
#define debug3(x, y, z) {cerr <<#x <<" = " <<x <<", "<<#y <<" = " <<y <<", "<<#z<<" = "<<z<<"\n";}
#define debugv(x) {{cerr <<#x <<" = "; FORE(itt, (x)) cerr <<*itt <<", "; cerr <<"\n"; }}
using std::cerr;
#else
#define debug(x)
#define debug2(x, y)
#define debug3(x, y, z)
#define debugv(x)
#define cerr if(0)cout
#endif
#define make(type, x) type x; cin>>x;
#define make2(type, x, y) type x, y; cin>>x>>y;
#define make3(type, x, y, z) type x, y, z; cin>>x>>y>>z;
#define make4(type, x, y, z, t) type x, y, z, t; cin>>x>>y>>z>>t;
using std::endl;
using std::cout;
using std::cin;
using std::vector;
using std::set;
using std::map;
using std::pair;
using std::max;
using std::min;
using std::ostream;
using std::fixed;
using std::ios_base;
using std::setprecision;
using std::make_pair;
using std::string;
using std::multiset;
using std::next_permutation;
using std::prev_permutation;
using std::random_shuffle;
using std::greater;
using std::lower_bound;
using std::upper_bound;
using std::reverse;
using std::swap;
using std::complex;
using std::sort;
using std::bitset;
using std::unordered_set;
typedef long long ll;
typedef long double LD;
typedef pair<int, int> PII;
typedef pair<ll, ll> PLL;
typedef vector<int> VI;
typedef vector<ll> VLL;
typedef vector<pair<int, int> > VPII;
typedef vector<pair<ll, ll> > VPLL;

template<class C> void mini(C&a4, C b4){a4=min(a4, b4); }
template<class C> void maxi(C&a4, C b4){a4=max(a4, b4); }
template<class T1, class T2>
ostream& operator<< (ostream &out, pair<T1, T2> pair) { return out << "(" << pair.first << ", " << pair.second << ")";}

const int N = 15;
unordered_set<int> dp[1 << N][N];
int dis[N][N];
int n, l;
int full_mask;
void Dfs(int mask, int v, int used, int len) {
  if (2 * used + 1 >= n) {
    dp[mask][v].insert(len);
    if (v != 1) {
      int cor_mask = full_mask - mask + (1 << (v - 2));
      if (dp[cor_mask][v].count(l - len)) {
        cout<<"possible"<<endl;
        exit(0);
      }
    }
  }
  if (2 * used >= n) {
    return;
  }
  FOR (nei, 2, n) {
    int nei_bit = nei - 2;

    if (((1 << nei_bit) & mask) == 0) {
      int new_mask = mask + (1 << nei_bit);
      if (len + dis[v][nei] <= l) {
        Dfs(new_mask, nei, used + 1, len + dis[v][nei]);
      }
    }
  }
}

#undef int
int main() {
#define int long long

  ios_base::sync_with_stdio(0);
  cout << fixed << setprecision(10);
  beg_clock = 1.0 * clock() / CLOCKS_PER_SEC;
  TimeStamp();
  cin>>n>>l;
  RE (i, n) {
    RE (j, n) {
      cin>>dis[i][j];
    }
  }
  full_mask = (1 << (n - 1)) - 1;
  Dfs(0, 1, 0, 0);
  cout<<"impossible\n";
  
  return 0;
}