#include <bits/stdc++.h>
//#include <atcoder/all>
using namespace std;
//using namespace atcoder;
//using mint = modint1000000007;
//const int mod = 1000000007;
//using mint = modint998244353;
//const int mod = 998244353;
//const int INF = 1e9;
//const long long LINF = 1e18;
#define rep(i, n) for (int i = 0; i < (n); ++i)
#define rep2(i,l,r)for(int i=(l);i<(r);++i)
#define rrep(i, n) for (int i = (n-1); i >= 0; --i)
#define rrep2(i,l,r)for(int i=(r-1);i>=(l);--i)
#define all(x) (x).begin(),(x).end()
#define allR(x) (x).rbegin(),(x).rend()
#define endl "\n"
#define P pair<int,int>
#define debug(v){{rep(_,v.size())cout << v[_] <<" ";}cout<< endl;}
template<typename A, typename B> inline bool chmax(A& a, const B& b) { if (a < b) { a = b; return true; } return false; }
template<typename A, typename B> inline bool chmin(A& a, const B& b) { if (a > b) { a = b; return true; } return false; }
int main() {
	ios::sync_with_stdio(false);
	cin.tie(nullptr);
	int n, m, k; cin >> n >> m >> k;
	int x = (k + 2) / 2;
	int y = k - x + 1;
	if ((n >= x) && (m >= y)) {//0101010101.......
		vector<int>v0(x, 1), v1(y, 1);
		if(x)v0[0] += n - x;
		if(y)v1.back() += m - y;
		string s;
		rep(i, x) {
			rep(j, v0[i])s += '0';
			if (v1.size() > i) rep(j, v1[i])s += '1';
		}
		cout << s << endl;
		return 0;
	}
	swap(x, y);
	if ((n >= x) && (m >= y)) {//10101010101.......
		vector<int>v0(x, 1), v1(y, 1);
		if(x)v0[0] += n - x;
		if(y)v1.back() += m - y;
		string s;
		rep(i, y) {
			rep(j, v1[i])s += '1';
			if (v0.size() > i) rep(j, v0[i])s += '0';
		}
		cout << s << endl;
		return 0;
	}
	cout << -1 << endl;
	return 0;
}