import java.util.Arrays;
import java.util.LinkedList;
import java.util.Scanner;

public class Main {
	
	public static long[][] mat_mul(int m, long[][] mat, long p){
		if(p == 0){
			return new long[m][m];
		}else if(p == 1){
			return mat;
		}else if(p % 2 == 1){
			return mat_max(m, mat, mat_mul(m, mat, p - 1));
		}else{
			long[][] ret = mat_mul(m, mat, p / 2);
			return mat_max(m, ret, ret);
		}
	}
	
	public static long[][] mat_max(int m, long[][] mat1, long[][] mat2){
		long[][] ret = new long[m][m];
		
		for(int from = 0; from < m; from++){
			for(int to = 0; to < m; to++){
				for(int i = 0; i < m; i++){
					ret[from][to] = Math.max(ret[from][to], mat1[from][i] + mat2[i][to]);
				}
			}
		}
		
		return ret;
	}
	
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		
		final int n = sc.nextInt();
		final int m = sc.nextInt();
		
		long[][] mat = new long[m][m];
		for(int i = 0; i < m; i++){
			for(int j = 0; j < m; j++){
				mat[i][j] = sc.nextLong();
			}
		}
		
		long[][] ret = mat_mul(m, mat, n - 1);
		
		long max = 0;
		for(int i = 0; i < m; i++){
			for(int j = 0; j < m; j++){
				//System.out.print(ret[i][j] + " ");
				max = Math.max(max, ret[i][j]);
			}
			//System.out.println();
		}
		
		System.out.println(max);
	}
}