#include <iostream>
#include <algorithm>
#include <vector>
#include <deque>
#include <queue>
#include <set>
#include <map>
#include <limits>
#include <cmath>
#include <iomanip>
#include <functional>
#include <random>
#include <set>
#include <atcoder/string>
#include <unordered_map>
#include <climits>
#include <atcoder/lazysegtree>

using namespace std;
using ll = long long;
using namespace atcoder;

int solve()
{
    ll N,M,K;
    cin >> N >> M >> K;
    if (2 *min(N,M) - 1 + (N != M) < K || (K == 0 && N > 0 && M > 0)){
        cout << -1 << endl;
    }else{
        vector<pair<char,ll>> runlength;
        if (K <  2 *min(N,M) - 1 + (N != M) || N >= M){
            runlength.push_back({'0',1});
            N--;
            for(int i = 0;i < K;i++){
                if (i % 2 == 0){
                    runlength.push_back({'1',1});
                    M--;
                }else{
                    runlength.push_back({'0',1});
                    N--;
                }
            }
            runlength[0].second += N;
            if (runlength[runlength.size()-1].first == '1'){
                runlength[runlength.size()-1].second += M;
            }else{
                runlength[runlength.size()-1].second += M;
            }
        }else{
            runlength.push_back({'1',1});
            M--;
            for(int i = 0;i < K;i++){
                if (i % 2 == 1){
                    runlength.push_back({'1',1});
                    M--;
                }else{
                    runlength.push_back({'0',1});
                    N--;
                }
            }
            runlength[0].second += M;
            runlength[1].second += N;
        }
        for(auto p:runlength){
            for(int i = 0;i < p.second;i++){
                cout << p.first;
            }
        }
        cout << endl;
    }
    return 0;
}
int main()
{
    // ll T;
    // cin >> T;
    // while (T--)
    // {
        solve();
    // }
    // cout << flush;
    return 0;
}