#include <iostream>
#include <algorithm>
#include <map>
#include <set>
#include <queue>
#include <stack>
#include <numeric>
#include <bitset>
#include <cmath>

static const int MOD = 1000000007;
using ll = long long;
using u32 = unsigned;
using u64 = unsigned long long;
using namespace std;

template<class T> constexpr T INF = ::numeric_limits<T>::max()/32*15+208;

template <class T, class U>
vector<T> make_v(U size, const T& init){ return vector<T>(static_cast<size_t>(size), init); }

template<class... Ts, class U>
auto make_v(U size, Ts... rest) { return vector<decltype(make_v(rest...))>(static_cast<size_t>(size), make_v(rest...)); }

template<class T> void chmin(T &a, const T &b){ a = (a < b ? a : b); }
template<class T> void chmax(T &a, const T &b){ a = (a > b ? a : b); }

int main() {
    int n, m;
    while(cin >> n >> m, n){
        auto dp = make_v(m, n, 0.0);
        auto G = make_v(n, n, 0.0);
        for (int i = 0; i < n; ++i) {
            for (int j = 0; j < n; ++j) {
                cin >> G[i][j];
            }
        }
        for (int i = 0; i < n; ++i) {
            dp[0][i] = 1.0;
        }
        for (int i = 0; i < m-1; ++i) {
            for (int j = 0; j < n; ++j) {
                for (int k = 0; k < n; ++k) {
                    chmax(dp[i+1][k],dp[i][j]*G[j][k]);
                }
            }
        }
        printf("%.2lf\n", *max_element(dp.back().begin(),dp.back().end()));
    }
    return 0;
}
