#include <bits/stdc++.h>
using namespace std;

#ifdef _RUTHEN
#include <debug.hpp>
#else
#define show(...) true
#endif

using ll = long long;
#define rep(i, n) for (int i = 0; i < (n); i++)
template <class T> using V = vector<T>;

int main() {
    ios::sync_with_stdio(false);
    cin.tie(0);
    int N, M, K;
    cin >> N >> M >> K;
    V<string> ans;
    {
        V<pair<int, int>> B(K + 1);
        int c[2] = {};
        rep(i, K + 1) {
            B[i] = {i % 2, 1};
            c[i % 2]++;
        }
        if (c[0] <= N and c[1] <= M) {
            rep(i, K + 1) {
                if (i % 2 == 0) {
                    B[i].second += N - c[0];
                    c[0] = N;
                }
            }
            for (int i = K; i >= 0; i--) {
                if (i % 2 == 1) {
                    B[i].second += M - c[1];
                    c[1] = M;
                }
            }
            if (c[0] == N and c[1] == M) {
                string s;
                for (auto &[c, cnt] : B) s += string(cnt, c + '0');
                ans.push_back(s);
            }
        }
    }
    {
        V<pair<int, int>> B(K + 1);
        int c[2] = {};
        rep(i, K + 1) {
            B[i] = {(i + 1) % 2, 1};
            c[(i + 1) % 2]++;
        }
        if (c[0] <= N and c[1] <= M) {
            rep(i, K + 1) {
                if ((i + 1) % 2 == 0) {
                    B[i].second += N - c[0];
                    c[0] = N;
                }
            }
            for (int i = K; i >= 0; i--) {
                if ((i + 1) % 2 == 1) {
                    B[i].second += M - c[1];
                    c[1] = M;
                }
            }
            if (c[0] == N and c[1] == M) {
                string s;
                for (auto &[c, cnt] : B) s += string(cnt, c + '0');
                ans.push_back(s);
            }
        }
    }
    sort(ans.begin(), ans.end());
    if (ans.size() == 0) {
        cout << -1 << '\n';
    } else {
        cout << ans[0] << '\n';
    }
    return 0;
}