#include "bits/stdc++.h"

using namespace std;

void solve() {
    int n;
    cin >> n;
//    vector<string> mp(n + 1);
    vector<bitset<5007>> edge(n + 1), goals(n + 1);
    vector<int> du(n + 1);
    for (int i = 1; i <= n; i++) {

        string s;
        cin >> s;
        for (int j = 1; j <= n; j++) {
            if (s[j - 1] == '1') {
                edge[i][j] = true;
                du[i]++;
            }
        }
        goals[i] = edge[i];
    }

    priority_queue<pair<int, int>> pq;
    for (int i = 1; i <= n; i++) {
        pq.emplace(du[i], i);
    }
    vector<int> ans;
    while (ans.size() <3 && !pq.empty()) {
        auto [_, i] = pq.top();
        pq.pop();
        for (int j = 1; j <= n; j++) {
            if (edge[i][j]) {
                goals[i] |= edge[j];
            }
        }
        goals[i][i] = false;
        if (goals[i].count() == n - 1)ans.emplace_back(i);
    }
    if(ans.size() <3) {
        cout << "NOT FOUND";
        return;
    }
    for (auto i: ans) cout << i << " ";

}

int main() {
    ios::sync_with_stdio(false), cin.tie(0);
    int t = 1;
    //cin >> t;
    while (t--) {
        solve();
    }

}
//6
//011010
//000101
//010111
//100001
//010100
//100010