#include <bits/stdc++.h>
using namespace std;
#if __has_include(<atcoder/all>)
#include <atcoder/all>
using namespace atcoder;
typedef modint998244353 mint;
#endif
typedef long long  ll;
typedef pair<int,int> pii; typedef pair<ll,ll> pll;
const int INF = 1e9; const long long LINF = 1e18;
const int MOD = 998244353; const int MOD1 = 1e9+7;
#define rep(i,n) for(int i=0;i<(int)(n);i++)
#define all(x) x.begin(), x.end()
template<typename T> bool chmin(T& a, T b){if(a > b){a = b; return true;} return false;}
template<typename T> bool chmax(T& a, T b){if(a < b){a = b; return true;} return false;}
void yorn(bool ans){cout << (ans?"Yes":"No") << endl; return;}

int main(){
    int n,m,k; cin >> n >> m >> k;
    int maxi,mini;
    if(min(n,m)==0) mini = 0;
    else mini = 1;
    if(n==m) maxi = 2*n-1;
    else maxi = min(n,m)*2;
    if(k<mini || maxi<k){cout << -1 << endl; return 0;}

    bool many0 = true;
    if(m>n){
        many0 = false;
        swap(n,m);
    } // n>m になり、0が多くなる

    vector<int> ans;
    int x = (k+1)/2;
    if(k==maxi && n!=m){
        rep(i,x){
            ans.push_back(0); ans.push_back(1);
        }
        ans.push_back(0);
    }
    else{
    rep(i,n-x) ans.push_back(0);
    rep(i,x){
        ans.push_back(0); ans.push_back(1);
    }
    rep(i,m-x) ans.push_back(1);
    }

    if(many0) rep(i,n+m) cout << ans.at(i);
    else rep(i,n+m) cout << 1-ans.at(i);
}