#include <iostream>
using namespace std;

int main()
{
    int i=0,j=0,k=0,l,r;
    char a;
    string s,s1,s2;
    while(cin>>a)
    {
        if(a!=',')
        {
            if(i==0) s+=a;
            else if(i==1) s1+=a;
            else s2+=a;
        }
        else i++;
    }
    for(i=0;i<s.length();i++)
    {
        while(s[i+j]==s1[j]&&j<s1.length()) j++;
        if(j==s1.length()) {l=i+j;break;}
        j=0;
    }
    if(i==s.length()-1&&j!=s1.length()) {cout<<"-1";return 0;}

    for(j=s.length()-1;j>=i+1;j--)
    {
        while(s[j+k]==s2[k]&&k<s2.length()) k++;
        if(k==s2.length()) {r=j-1;break;}
        k=0;
    }
    if(j==s.length()-1&&k!=s2.length()) {cout<<"-1";return 0;}
    if(r<l) cout<<"-1";
    else cout<<r-l+1;
    return 0;
}