#include <bits/stdc++.h>
using namespace std;
#include <atcoder/all>
using namespace atcoder;
//using mint = static_modint<998244353>;
//using mint = modint;
using mint = static_modint<1000000007>;
using vm = vector<mint>;
using vvm = vector<vm>;
ostream &operator<<(ostream &o,const mint &m){cout<<m.val();return o;}
using ll = long long;
using vl = vector<ll>;
using vvl = vector<vl>;
using pl = pair<ll,ll>;
#define rep(i,n) for(ll i=0;i<(ll)(n);++i)
#define reps(i,s,n) for(ll i=(s);i<(ll)(n);++i)
#define rep1(i,n) for(ll i=1;i<=(ll)(n);++i)
#define ts(i) to_string(i)
#define chmin(x,y) x=min(x,y)
#define chmax(x,y) x=max(x,y)
const long long INF = 1e18;

#ifdef DEBUG
#include <debug.hpp>
#endif
string solve(){
	ll N,M,K;
	cin >> N>>M>>K;

	if(K==0){
		if(N>0&&M>0) return "-1";
	}
	string s="";
	if(N==1&&K==2){
		s="101";
		rep(i,M-2){
			s+='1';
		}
	}
	if(K%2){
		ll y=(K+1)/2;
		ll x=K+1-y;
		ll xx=x,yy=y;
		while(xx>0||yy>0){
			if(xx-->0)s+='0';
			if(yy-->0)s+='1';
		}
#ifdef DEBUG
		cout<<"s="<<s<<endl;
#endif
		if(N-x<0||M-y<0)return "-1";
		else{
			string tmp="";
			rep(i,N-x){
				tmp+='0';
			}
			s=tmp+s;
			rep(i,M-y){
				s+='1';
			}
		}
	}else{ //Even
		ll y=(K+1-2)/2;
		ll x=K+1-2-y;
		ll xx=x,yy=y;
		while(xx>0||yy>0){
			if(xx-->0)s+='0';
			if(yy-->0)s+='1';
		}
#ifdef DEBUG
		cout<<"s="<<s<<endl;
#endif
		if(N-x-1<0||M-y<0)return "-1";
		else{
			string tmp="";
			rep(i,N-x-1){
				tmp+='0';
			}
			s=tmp+s;
			rep(i,M-y){
				s+='1';
			}
			s+='0';
		}
	}
	return s;
}

int main(){
#ifdef DEBUG
	cout << "--- Input ---" << endl;
#endif
#ifdef DEBUG
	cout << "--- Answer ---" << endl;
#endif
	cout<<solve()<<endl;
}
//cout << fixed << setprecision(9);