#include<iostream>
#include<vector>
#include<string>
#include<algorithm>	
#include<map>
#include<set>
#include<utility>
#include<cmath>
#include<cstring>
#include<queue>
#include<cstdio>
#include<sstream>
#include<iomanip>
#define loop(i,a,b) for(int i=a;i<b;i++) 
#define rep(i,a) loop(i,0,a)
#define pb push_back
#define mp make_pair
#define all(in) in.begin(),in.end()
#define shosu(x) fixed<<setprecision(x)
using namespace std;
//kaewasuretyuui
typedef long long ll;
typedef pair<int,int> pii;
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef vector<pii> vp;
typedef vector<vp> vvp;
typedef pair<int,pii> pip;
typedef vector<pip>vip;
const double PI=acos(-1);
const double EPS=1e-8;
const int inf=1<<30;
int main(){
	int n,m;
	while(cin>>n>>m,n+m){
		double in[110][110]={0},dp[110][110]={0};
		rep(i,n)rep(j,n)cin>>in[i][j];
		rep(i,n)dp[0][i]=1;
		rep(i,m-1)rep(j,n)rep(k,n)
			dp[i+1][k]=max(dp[i+1][k],dp[i][j]*in[j][k]);
		double out=0;
		rep(i,n)out=max(out,dp[m-1][i]);
		cout<<shosu(2)<<out<<endl;
	}
}