#include<bits/stdc++.h>
#define REP(i,n) for(int i=0,i##_len=int(n);i<i##_len;++i)
#define rep(i,a,b) for(int i=int(a);i<int(b);++i)
#define All(x) (x).begin(),(x).end()
#define rAll(x) (x).rbegin(),(x).rend()
using namespace std;
using ll = long long;

int main(){
    int n[2],k;
    cin>>n[0]>>n[1]>>k;
    string s;
    if(n[0]>0) {
        s.push_back('0');
        n[0]-=1;
    }
    else {
        s.push_back('1');
        n[1] -= 1;
    }
    while (n[0] > 0 || n[1] > 0) {
        int num = s.back() - '0';
        if (k > 0) {
            num ^= 1;
            if(n[num] > 0){
                s.push_back(num + '0');
                n[num]--;
                k--;
            }
            else {
                break;
            }
        }
        else {
            break;
        }
    }
    cerr << s << " " << n[0] << " " << n[1] << " " << k << endl;
    string front(n[0],'0');
    string back(n[1], '1');
    if (s.back() == '0') {
        s.pop_back();
        back.push_back('0');
    }
    if(k > 0) {
        cout << "-1" << endl;
    }
    else {
        cout << front + s + back << endl;
    }
}