#define _CRT_SECURE_NO_WARNINGS
#include<iostream>
#include<cstdio>
#include<cstdlib>
#include<string>
#include<algorithm>
#include<cmath>
#include<queue>
#include<vector>
#include<stack>
using namespace std;

#define int long long
#define REP(i,n) for(int i=0;(i)<(n);(i)++)
#define ll long long

int dp[30][1000];
int n, m;
int A[40][40];

void makedp() {
	for (int i = 1;i < 1000;i++) {
		for (int j = 0;j < m;j++) {
			int tmp = 0;
			for (int k = 0;k < m;k++) {
				tmp = max(tmp, dp[k][i - 1] + A[k][j]);
			}
			dp[j][i] = tmp;
		}
	}

	/*
	REP(i,n+1){
		REP(j, m) {
			cout << dp[j][i] << " ";
		}
		cout << endl;
	}
	*/
}

signed main() {
	cin >> n >> m;
	REP(i, m) {
		REP(j, m) cin >> A[i][j];//0-indexed
	}

	makedp();

	int ans = 0;
	REP(i, m) ans = max(ans, dp[i][n-1]);

	cout << ans;

	return 0;
}