#include <bits/stdc++.h>

using i64 = long long;

int main() {
    std::ios::sync_with_stdio(false);
    std::cin.tie(nullptr);
    
    int N, M, K;
    std::cin >> N >> M >> K;
    
    if ((N && M && K < 1) || K > std::min({2 * N, 2 * M, N + M - 1})) {
        std::cout << -1 << "\n";
        return 0;
    }
    
    int last = -1;
    int cnt[2] = {N, M};
    for (int i = 0; i < N + M; i++) {
        for (int t = 0; t < 2; t++) {
            if (cnt[t] == 0) {
                continue;
            }
            int newK = K - (!t == last);
            if (newK < (cnt[!t] > 0) || newK > std::min({2 * cnt[t] - 1, 2 * cnt[!t], cnt[t] + cnt[!t] - 1})) {
                continue;
            }
            K = newK;
            cnt[t] -= 1;
            std::cout << t;
            last = t;
            break;
        }
    }
    std::cout << "\n";
    
    return 0;
}