#include <bits/stdc++.h>
#define ll long long
#define INF 1000000005
#define MOD 1000000007
#define EPS 1e-10
#define rep(i,n) for(int i=0;i<(int)n;++i)
#define each(a,b) for(auto (a): (b))
#define all(v) (v).begin(),(v).end()
#define zip(v) sort(all(v)),v.erase(unique(all(v)),v.end())
#define fi first
#define se second
#define pb push_back
#define show(x) cout<<#x<<" = "<<(x)<<endl
#define spair(p) cout<<#p<<": "<<p.fi<<" "<<p.se<<endl
#define svec(v) cout<<#v<<":";rep(kbrni,v.size())cout<<" "<<v[kbrni];cout<<endl
#define sset(s) cout<<#s<<":";each(kbrni,s)cout<<" "<<kbrni;cout<<endl
#define smap(m) cout<<#m<<":";each(kbrni,m)cout<<" {"<<kbrni.first<<":"<<kbrni.second<<"}";cout<<endl

using namespace std;

typedef pair<int,int>P;

const int MAX_N = 100005;

ll dp[35][31][31];
ll ans[31][31];
ll tmp[31][31];

int main()
{
    cin.tie(0);
    ios::sync_with_stdio(false);
    int n,m;
    cin >> n >> m;
    n--;
    rep(i,m){
        rep(j,m){
            cin >> dp[0][i][j];
        }
    }
    rep(i,34){
        rep(j,m){
            rep(k,m){
                rep(l,m){
                    dp[i+1][j][k] = max(dp[i+1][j][k],dp[i][j][l] + dp[i][l][k]);
                }
            }
        }
    }
    int cnt = 0;
    while(n){
        if(n & 1){
            rep(i,m){
                rep(j,m){
                    tmp[i][j] = ans[i][j];
                }
            }
            rep(i,m){
                rep(j,m){
                    ll res = 0;
                    rep(k,m){
                        res = max(res,tmp[i][k]+dp[cnt][k][j]);
                    }
                    ans[i][j] = res;
                }
            }
        }
        cnt++;
        n >>= 1;
    }
    ll mx = 0;
    rep(i,m){
        rep(j,m){
            mx = max(mx,ans[i][j]);
        }
    }
    cout << mx << endl;
    return 0;
}