#include <iostream>
using namespace std;
int main () {
string s, s1, s2;
int t = 0;
char a;
while (cin >> a) {
if (a != ',') {
if (t == 0)
s += a;
else if (t == 1)
s1 += a;
else
s2 += a;
} else
t ++;
}
int l, l1, l2;
l1 = s.find(s1);
l2 = s.rfind(s2);
if (l1 != -1 && l2 != -1 && l1 + s1.size() <= l2) {
cout << l2 - l1 - s1.size();
} else
cout << -1;
}