#include <bits/stdc++.h>
#define ll long long
using namespace std;
ll gcd(ll a,ll b) { if (b==0) return a; return gcd(b,a%b); }
ll lcm(ll a,ll b) { return a/gcd(a,b)*b; }
ll solve(string s)
{
    ll n=s.size();
    vector<ll>c;
    for(ll i=0;i<n;i++)
        if(s[i]=='1') c.push_back(i+1);    
    ll ans=c[0];
    for(ll i=0;i<c.size();i++) ans=lcm(ans,c[i]);
    if(s=="01" or c.size()==0) return -1;
    return ans;    
    
}
signed main() 
{
    string s; cin>>s;
    cout<<solve(s);
    return 0;
}

#include <bits/stdc++.h>
#define ll long long
using namespace std;
ll count(ll k,vector<ll>&a,vector<ll>&b)
{
    ll n=a.size();
    ll m=b.size();
    unordered_map<ll,ll>mpp;
    ll ans=0;
    for(ll i=0;i<n;i++) mpp[__gcd(a[i],k)]++;
    for(ll i=0;i<m;i++)
    {
        for (auto &it:mpp)
            if((__gcd(b[i],k)*it.first)%k==0) ans+=it.second;
    }
        return ans;
}
signed main() 
{
    ll n,m,k; cin>>n>>m>>k;
    vector<ll>a(n),b(m);
    for(ll i=0;i<n;i++) cin>>a[i];
    for(ll i=0;i<m;i++) cin>>b[i];
    cout<<count(k,a,b);
    return 0;
}