#line 2 "/home/penguin8331/vscode/library/template/template.hpp"
#include <bits/stdc++.h>
#line 3 "/home/penguin8331/vscode/library/template/macro.hpp"

#define pb push_back
#define mp make_pair
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
#define elif else if
#define updiv(N, X) (((N) + (X) - (1)) / (X))
#define sigma(a, b) ((a + b) * (b - a + 1) / 2)
#line 3 "/home/penguin8331/vscode/library/template/alias.hpp"

using ll = long long;
using ld = long double;
using pii = std::pair<int, int>;
using pll = std::pair<ll, ll>;
constexpr int inf = 1 << 30;
constexpr ll INF = 1LL << 60;
constexpr int dx[] = {1, 0, -1, 0, 1, -1, 1, -1};
constexpr int dy[] = {0, 1, 0, -1, 1, 1, -1, -1};
constexpr int mod = 998244353;
constexpr int MOD = 1e9 + 7;
#line 3 "/home/penguin8331/vscode/library/template/func.hpp"

template <typename T>
inline bool chmax(T& a, T b) { return ((a < b) ? (a = b, true) : (false)); }
template <typename T>
inline bool chmin(T& a, T b) { return ((a > b) ? (a = b, true) : (false)); }
#line 3 "/home/penguin8331/vscode/library/template/util.hpp"

struct IOSetup {
    IOSetup() {
        std::cin.tie(nullptr);
        std::ios::sync_with_stdio(false);
        std::cout.tie(0);
        std::cout << std::fixed << std::setprecision(12);
        std::cerr << std::fixed << std::setprecision(12);
    }
} IOSetup;
#line 1 "/home/penguin8331/vscode/library/template/debug.hpp"
#ifdef LOCAL
#include <algo/debug.hpp>
#else
#define debug(...)
#endif
#line 8 "/home/penguin8331/vscode/library/template/template.hpp"
using namespace std;
#line 2 "A.cpp"

int main() {
    int N, M, K;
    cin >> N >> M >> K;
    // 00000 0 1 0 1 0 1 0 1 111111
    if (min(min(N, M) * 2, N + M - 1) < K) {
        cout << -1 << endl;
        return 0;
    }
    if ((N == 0 || M == 0) && K > 0) {
        cout << -1 << endl;
        return 0;
    }
    int fzero = 0, lone = 0;
    while (true) {
        if (min(min(N - 1, M) * 2, N + M - 2) < K) {
            break;
        }
        N--;
        fzero++;
    }
    while (true) {
        if (min(min(N, M - 1) * 2, N + M - 2) < K) {
            break;
        }
        M--;
        lone++;
    }
    debug(fzero, lone, N, M);
    for (int i = 0; i < fzero; i++) {
        debug(i);
        cout << 0;
    }
    if (N != M) {
        if (N > M) {
            cout << 0;
            N--;
        } else {
            cout << 1;
            M--;
        }
    }
    for (int i = 0; i < N; i++) {
        cout << "01";
    }
    for (int i = 0; i < lone; i++) {
        cout << 1;
    }
    cout << endl;
}