#ifndef LOCAL
#pragma GCC optimize("O3")
#endif
#include <bits/stdc++.h>
using namespace std;
#define sim template <class c
#define mor > muu & operator<<(
#define ris return *this
#define eni(r) sim> typename enable_if <1 r sizeof(dud<c>(0)),muu&>::type operator<<(c g) {
sim> struct rge {c b,e ;};
sim> rge<c> range(c i, c j) {return rge<c>{i, j};}
sim> auto dud(c *r)-> decltype(cerr << *r);
sim> char dud(...);
struct muu {
	#ifdef LOCAL
	stringstream a;
	~muu() {cerr << a.str() << endl;}
	eni(<) a << boolalpha << g; ris;}
	eni(==) ris << range(begin(g), end(g));}
	sim, class m mor pair<m,c> r) {ris << "(" << r.first << ", " << r.second << ")";}
	sim mor rge<c> u) {
		a << "[";
		for (c i = u.b; i != u.e; ++i)
			*this << ", " + 2 * (i == u.b) << *i;
		ris << "]";
	}
	#else
	sim mor const c&) {ris;}
	#endif
	muu & operator()(){ris;}
};
#define debug (muu() << __FUNCTION__ << "#" << __LINE__ << ": ")
#define imie(r) "[" #r ": " << (r) << "] "
#define imask(r) "[" #r ": " << bitset<8 * sizeof(r)>(r) << "] "
#define arr(a, i) "[" #a imie(i) ": " << a[i] << "] "
#define arr2(a, i, j) "[" #a imie(i) imie(j) ": " << a[i][j] << "] "
const int nax = 3e5 + 11;
unordered_set<int> hashes[nax];
vector <int> seen;
char in[nax], curr[nax], rans[nax];
using ll = long long;
ll pows[nax];
int jump[nax];
sim> void mini(c &a, c b) {
	if (a > b) a = b;
}
sim> void maxi(c &a, c b) {
	if (a < b) a = b;
}
const ll mod = 1e18 + 3, base = 12398173;
int nn;
ll mul(ll a, ll b) {
	return a * __int128(b) % mod;
}
void run(int len) {
	ll powe = pows[len];
	ll hash = 0;
	for (int i = 0; i < len; ++i)
		hash = mul(hash, base) + rans[i];
	hash %= mod;
	if (hashes[len].count(hash))
		maxi(jump[0], len);
	for (int i = 0; i + len < nn; ++i) {
		hash = mul(hash, base) - mul(rans[i], powe) + rans[i + len];
		hash %= mod;
		if (hash < 0) hash+=mod;
		if (hashes[len].count(hash))
			maxi(jump[i + 1], i + len + 1);
	}
}
int main() {
	pows[0] = 1;
	for (int i = 1; i < nax; ++i)
		pows[i] = mul(pows[i - 1], base);
	int l;
	scanf("%d", &l);
	scanf("%s", rans);
	nn = strlen(rans);
	for (int i = 0; i < l; ++i) {
		scanf("%s", curr);
		int n = strlen(curr);
		ll hash = 0;
		for (int i = 0; i < n; ++i)
			hash = mul(hash, base) + curr[i];
		hash %= mod;
		hashes[n].insert(hash);
	}
	for (int i = 0; i < nax; ++i)
		jump[i] = i;
	for (int i = 0; i < nax; ++i)
		if (hashes[i].size())
			run(i);
	for (int i = 1; i <= nn; ++i)
		maxi(jump[i], jump[i - 1]);
	debug() << range(jump, jump + nn + 1);
	int where = 0;
	int ans = 0;
	while (where < nn) {
		int to = jump[where];
		if (to == where) {
			ans = -1;
			break;
		}
		where = to;
		ans++;
		debug << imie(where);
	}
	printf("%d\n", ans);
}
/*
 * main#93: [2, 1, 2, 5, 4, 5]
main#106: [where: 2] 
2
abbab
ab
bbb
*/