#include<iostream>
#include<cstdio>
#include<vector>
#include<map>
#include<tuple>
#include<string>
#include<cmath>
#include<climits>
#include<algorithm>
#include<bitset>
#include<set>
#include<stack>
using namespace std;  
typedef long long ll;
typedef vector<int> vi;
typedef vector<vi> vvi;
#define rep(i,n) for(ll i=0;i<(n);i++)  
#define tii tuple<int,int>
#define tiii tuple<int,int,int>
#define mt make_tuple
#define pb push_back  
#define ALL(a) (a).begin(),(a).end()
#define FST first
#define SEC second  
const int INF = (INT_MAX/2);
const ll LLINF = (LLONG_MAX/2);
const double eps = 1e-5;
const double PI = M_PI;  
#define DEB cerr<<"!"<<endl
#define SHOW(a,b) cerr<<(a)<<" "<<(b)<<endl
#define SHOWARRAY(ar,i,j) REP(a,i)REP(b,j)cerr<<ar[a][b]<<((b==j-1)?((a==i-1)?("\n\n"):("\n")):(" "))
#define DIV 1000000007
ll pow(ll x,ll n,ll m){ll r=1;while(n>0){if((n&1)==1)r=r*x%m;x=x*x%m;n>>=1;}return r%m;}
typedef vector<ll> Array;
typedef vector<Array> Matrix;

int n,m; 
// O(n)
Matrix identity(int n) {
  Matrix A(n, Array(n));
  rep(i,n) A[i][i] = 0;
  return A;
}
// O(n^2)
Array mul(const Matrix &A, const Array &x){
  Array y(A.size());
  rep(i,A.size())rep(j,A[0].size())  y[i] = A[i][j] * x[j];
  return y;
}
// O(n^3)
Matrix mul(const Matrix &A, const Matrix &B) {
  Matrix C(A.size(), Array(B[0].size()));
  rep(i,C.size())rep(j,C[i].size())rep(k,A[i].size())
    C[i][j] = max(C[i][j],A[i][k] + B[k][j]);
  return C;
}
// O(n^3 log e)
Matrix pow(const Matrix &A, int e) {
  return e == 0 ? identity(A.size())  :
     e % 2 == 0 ? pow(mul(A, A), e/2) : mul(A, pow(A, e-1));
}

int main(){
  cin >> n >> m;
  Matrix mat(m,Array(m));
  rep(i,m)rep(j,m) cin >> mat[i][j];
  mat = pow(mat,n-1);
  ll ans = 0;
  //rep(i,m){rep(j,m)cout << " " << mat[i][j]; cout << endl;}
  rep(i,m)rep(j,m) ans = max(ans,mat[i][j]);
  cout << ans << endl;
}