#include<iostream>
#include<vector>
#include<algorithm>
using namespace std;
using ll=long long;
#define all(v) v.begin(),v.end()
#define rall(v) v.rbegin(),v.rend()
template<class T> bool chmax(T &a, T b){if (a < b){a = b;return true;} else return false;}
template<class T> bool chmin(T &a, T b){if (a > b){a = b;return true;} else return false;}

int main(){
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    int N,M,K;
    cin>>N>>M>>K;
    if(K==0){
        if(N==0)while(M--)cout<<1;
        else if(M==0)while(N--)cout<<0;
        else cout<<-1;
        cout<<"\n";
    }else if(K%2==1){
        K++;
        if(N<K/2||M<K/2)cout<<-1;
        else{
            for(int i=0;i<N-K/2;i++)cout<<0;
            for(int i=0;i<K/2;i++)cout<<"01";
            for(int i=0;i<M-K/2;i++)cout<<1;
        }
        cout<<"\n";
    }else{
        if(N==K/2&&M>K/2){
            for(int i=0;i<K/2;i++)cout<<"10";
            for(int i=0;i<M-K/2;i++)cout<<1;
        }else if(N>K/2&&M>=K/2){
            for(int i=0;i<N-K/2;i++)cout<<0;
            for(int i=0;i<K/2-1;i++)cout<<"10";
            for(int i=0;i<M-K/2+1;i++)cout<<1;
            cout<<0;
        }else{
            cout<<-1;
        }
        cout<<"\n";
    }
}