#include <bits/stdc++.h>
#define endl '\n'
#define all(a) (a).begin(), (a).end()
#define len(a) (int) (a).size()
#define forn(i, n) for (int (i) = 0; (i) < (n); ++(i))
#define int long long
using namespace std;
void solve();
mt19937 rnd(2009);
signed main(){

#ifdef LOCAL
    freopen("input.txt", "r", stdin);
    freopen("output.txt", "w", stdout);
#else
    mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
    swap(rng, rnd);
#endif
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);

    solve();
}



int get_small(int mask, int sub){
    int cur = 0, res = 0;
    forn (i, 61){
        if ((mask >> i)&1){
            res *= 2;
            res += (sub >> i)&1;
            cur++;
        }
    }
    return res;
}

int n, m, p;
string get_big(int mask, int sub){
    int cur = 0;
    string res;
    forn (i, m){
        if ((mask >> (m - i - 1))&1){
            res += (char) ('0' + ((sub >> cur)&1));
            cur++;
        }
        else {
            res += '0';
        }
    }
    return res;
}






void solve() {
    cin >> n >> m >> p;
    vector<int> a(n);
    forn (i, n){
        string s; cin >> s;
        for (auto j : s){
            a[i] *= 2;
            a[i] += (j == '1');
        }
    }
    shuffle(all(a), rnd);
    string bst; forn (i, m) bst += '0';
    /*
    for (auto i : a){
        cout << i << endl;
    }*/
    forn (qwe, min(40ll, n)){
        int mask = a[qwe];
        int lng = __builtin_popcountll(mask);
        vector<int> vals(1ll << lng);
        for (auto i : a){
            vals[((1ll << lng) - 1) ^ get_small(mask, mask&i)]++;
        }
        for (int k = 0; k < lng; k++) {
            for (int msk = 0; msk < (1 << lng); msk++)
                if ((msk >> k) & 1)
                    vals[msk] += vals[msk ^ (1 << k)];
        }
        vector<int> vals2(1ll << lng);
        forn (msk, 1ll << lng){
            vals2[msk] = vals[((1ll << lng) - 1) ^ msk];
        }
        vals = vals2;
        forn (msk, 1ll << lng){
            if (vals[msk] * 2 >= n){
                auto cur = get_big(mask, msk);
                /*
                if (cur == "1000"){
                    cout << mask << endl;
                    cout << msk << endl;
                    for (auto i : vals){
                        cout << i << ' ';
                    }
                    cout << endl;
                }*/
                if (count(all(cur), '1') > count(all(bst), '1'))
                    bst = cur;
            }
        }
    }
    cout << bst << endl;
}