#include <iostream>
#include <atcoder/all>

#define ALL(V) std::begin(V), std::end(V)

std::string solve(int N, int M, int K) {
    if (N == 0 || M == 0) {
        if (K == 0) {
            char c = '0' + (M == 0);
            return std::string(N + M, c);
        } else {
            return "-1";
        }
    }

    if (K == 0) return "-1";
    int max = std::min(N, M) * 2 - (N == M);
    if (max < K) return "-1";
    if (K == max && N < M) {
        std::string s;
        for (int i = 0; i < N; i++) s += "10";
        s += std::string(M - N, '1');
        return s;
    }

    std::string ans = "01";
    N--; M--; K--;
    while (2 <= K) {
        assert(N && M);
        ans += "01";
        K -= 2;
        N--; M--;
    }
    ans += std::string(M, '1');
    if (K == 1) {
        assert(N);
        ans += '0';
        N--;
    }
    return std::string(N, '0') + ans;
}

int main() {
    int N, M, K;
    std::cin >> N >> M >> K;
    std::cout << solve(N, M, K) << std::endl;
    return 0;
}