#include <iostream>
#include <algorithm>
#include <iomanip>
#include <vector>
#include <queue>
#include <deque>
#include <set>
#include <map>
#include <tuple>
#include <cmath>
#include <numeric>
#include <functional>
#include <cassert>

#define debug_value(x) cerr << "line" << __LINE__ << ":<" << __func__ << ">:" << #x << "=" << x << endl;
#define debug(x) cerr << "line" << __LINE__ << ":<" << __func__ << ">:" << x << endl;

template<class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return 1; } return 0; }
template<class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return 1; } return 0; }

using namespace std;
typedef long long ll;

template<typename T>
vector<vector<T>> vec2d(int n, int m, T v){
    return vector<vector<T>>(n, vector<T>(m, v));
}

template<typename T>
vector<vector<vector<T>>> vec3d(int n, int m, int k, T v){
    return vector<vector<vector<T>>>(n, vector<vector<T>>(m, vector<T>(k, v)));
}

template<typename T>
void print_vector(vector<T> v, char delimiter=' '){
    if(v.empty()) {
        cout << endl;
        return;
    }
    for(int i = 0; i+1 < v.size(); i++) cout << v[i] << delimiter;
    cout << v.back() << endl;
}

int main(){
    ios::sync_with_stdio(false);
    cin.tie(0);
    cout << setprecision(10) << fixed;
    int n, m, k; cin >> n >> m >> k;
    // 0ではじめられるか
    int min0 = k/2+1, min1 = (1+k)/2;
    if(min0 <= n && min1 <= m){
        string ans;
        ans += string(n-min0, '0');
        int nx = 0;
        for(int i = 0; i < k+1; i++){
            ans += '0'+nx;
            nx ^= 1;
        }
        string tail;
        while(ans.back() == '0' && !ans.empty()){
            tail += ans.back(); ans.pop_back();
        }
        ans += string(m-min1, '1');
        ans += tail;
        cout << ans << endl;
        return 0;
    }
    // 1ではじめられるか
    min1 = k/2+1, min0 = (1+k)/2;
    if(min0 <= n && min1 <= m){
        string ans = "1";
        if(n-min0 > 0) ans += string(n-min0, '0');
        int nx = 0;
        for(int i = 0; i < k; i++){
            ans += '0'+nx;
            nx ^= 1;
        }
        string tail;
        while(ans.back() == '0' && !ans.empty()){
            tail += ans.back(); ans.pop_back();
        }
        ans += string(m-min1, '1');
        ans += tail;
        cout << ans << endl;
        return 0;
    }
    cout << -1 << endl;
}