#include <cmath>
#include <vector>
#include <list>
#include <map>
#include <set>
#include <functional>
#include <queue>
#include <iostream>
#include <string.h>
#include <iomanip>
#include <algorithm>
#include <functional>
#include <cstdint>
#include <climits>
#include <unordered_set>
#include <sstream>
#include <stack>

using namespace std;

typedef long long int ll;
typedef pair<ll,ll> pii;
typedef tuple<ll,ll,ll> t3;

using namespace std;

ll n, m;
vector<vector<vector<ll>>> mat;

vector<vector<ll>> add(const vector<vector<ll>>& s)
{
    auto p = vector<vector<ll>>(m, vector<ll>(m, 0));
    for(int y1 = 0;y1 < m;y1++)
    {
        for(int x1 = 0;x1 < m;x1++)
        {
            for(int y2 = 0;y2 < m;y2++)
            {
                p[y1][x1] = max(p[y1][x1], s[y2][x1] + s[y1][y2]);
            }
        }
    }
    return p;
}

vector<vector<ll>> add(const vector<vector<ll>>& l,const vector<vector<ll>>& r)
{
    auto p = vector<vector<ll>>(m, vector<ll>(m, 0));
    for(int y1 = 0;y1 < m;y1++)
    {
        for(int x1 = 0;x1 < m;x1++)
        {
            for(int y2 = 0;y2 < m;y2++)
            {
                p[y1][x1] = max(p[y1][x1], l[y2][x1] + r[y1][y2]);
            }
        }
    }
    return p;
}

int main() {
    cin >> n >> m;
    mat.emplace_back();
    mat[0].assign(m, vector<ll>(m, 0));
    for(int y = 0;y < m;y++)
    {
        for(int x = 0;x < m;x++)
        {
            cin>> mat[0][y][x];
        }
    }
    for(int i = 1, j = 1;j <= n;i++, j*=2)
    {
        mat.emplace_back(add(mat[i-1]));
    }
    auto ret = vector<vector<ll>>(m, vector<ll>(m, 0));
    int i = 0;
    n--;
    while(n > 0)
    {
        if(n & 1)
        {
            ret = add(ret, mat[i]);
        }
        n>>=1;
        i++;
    }
    ll r = 0;
    for(int y = 0;y < m;y++)
    {
        for(int x = 0;x < m;x++)
        {
            r = max(r, ret[y][x]);
        }
    }
    cout << r << endl;    
    return 0;
}