#include<iostream>
#include<string>
#include<cstdio>
#include<vector>
#include<cmath>
#include<algorithm>
#include<functional>
#include<iomanip>
#include<queue>
#include<ciso646>
#include<random>
#include<map>
#include<set>
#include<complex>
#include<bitset>
#include<stack>
#include<unordered_map>
using namespace std;
typedef long long ll;
typedef unsigned int ui;
const ll mod = (ll)(1e+9) + 7;
const ll INF = (ll)1000000007 * 1000000007;
typedef pair<int, int> P;
#define stop char nyaa;cin>>nyaa;
#define rep(i,n) for(int i=0;i<n;i++)
#define per(i,n) for(int i=n-1;i>=0;i--)
#define Rep(i,sta,n) for(int i=sta;i<n;i++)
#define rep1(i,n) for(int i=1;i<=n;i++)
#define per1(i,n) for(int i=n;i>=1;i--)
#define Rep1(i,sta,n) for(int i=sta;i<=n;i++)
typedef long double ld;
typedef complex<ld> Point;
const ld eps = 1e-8;
const ld pi = acos(-1.0);
typedef pair<ll, ll> LP;
typedef pair<ld, ld> LDP;
int a[100][100];
bool used[100][100];
int dx[4] = { 1,0,-1,0 };
int dy[4] = { 0,1,0,-1 };
int main(){
	int w, h; cin >> w >> h;
	rep(i, h) {
		rep(j, w) {
			cin >> a[i][j];
		}
	}
	string ans = "impossible";
	rep(i, h) {
		rep(j, w) {
			if (used[i][j])continue;
			queue<pair<P, P>> q; q.push({ {i,j},{i,j} });
			used[i][j] = true;
			while (!q.empty()) {
				pair<P,P> nex = q.front(); q.pop();
				P x = nex.first,y=nex.second;
				rep(k, 4) {
					int nx = x.first + dx[k];
					int ny = x.second + dy[k];
					if (nx < 0 || nx >= h || ny < 0 || ny >= w)continue;
					if (y == P{nx, ny})continue;
					if (used[nx][ny] && a[nx][ny] == a[i][j]) {
						ans = "possible";
						cout << nx << " " << ny << endl;
					}
					else if (a[nx][ny] == a[i][j]) {
						used[nx][ny] = true;
						q.push({ {nx,ny},x });
					}
				}
			}
			//cout << i << " " << j << " " << ans << endl;
		}
	}
	cout << ans << endl;
	return 0;
}