#include <bits/stdc++.h>
using namespace std;
#define FOR(i, a, b) for (int i = (a); i < (b); i++)
#define int long long
const int64_t INF = 1ll << 60;
const int N = 1e6 + 5;
const int MOD[] = {(int) 1e9 + 7, (int) 1e9 + 9};
const int BASE = 37;
vector<array<int, 2>> hs[N], h[N];
int INV[2][N], lcp[N], P[2][N], n, m, H[2][N];
string L, s[N];
int inv(int x, const int MOD) {
int re = 1;
for (int b = MOD - 2; b; b >>= 1, x = x * x % MOD) if (b & 1)
re = re * x % MOD;
return re;
}
int get_hash(int i, int l, int r) {
int hsh = H[i][r] - (l ? H[i][l - 1] : 0);
hsh *= INV[i][l];
hsh %= MOD[i];
if (hsh < 0)
hsh += MOD[i];
return hsh;
}
bool check(int l, int r) {
return binary_search(hs[r - l].begin(), hs[r - l].end(), array<int, 2>{get_hash(0, l, r), get_hash(1, l, r)});
}
void build_lcp() {
FOR(i, 0, L.size()) {
int l = i - 1, r = L.size();
while (r - l > 1) {
int m = l + r >> 1;
if (check(i, m))
l = m;
else
r = m;
}
lcp[i] = r;
}
}
signed main() {
ios::sync_with_stdio(0), cin.tie(0);
P[0][0] = P[1][0] = INV[0][0] = INV[1][0] = 1;
FOR(j, 0, 2) {
FOR(i, 1, N) {
P[j][i] = (P[j][i - 1] * BASE) % MOD[j];
INV[j][i] = inv(P[j][i], MOD[j]);
}
}
cin >> n >> m;
FOR(i, 0, n) {
cin >> s[i];
h[i].resize(s[i].size());
h[i][0] = {s[i][0] - 'a' + 1, s[i][0] - 'a' + 1};
FOR(k, 0, 2) {
FOR(j, 1, s[i].size()) {
h[i][j][k] = (h[i][j - 1][k] + (s[i][j] - 'a' + 1) * P[k][j] % MOD[k]) % MOD[k];
}
}
FOR(j, 0, s[i].size())
hs[j].push_back(h[i][j]);
}
FOR(i, 0, N) {
sort(hs[i].begin(), hs[i].end());
}
cin >> L;
FOR(k, 0, 2) {
H[k][0] = L[0] - 'a' + 1;
FOR(i, 1, L.size()) {
H[k][i] = (H[k][i - 1] + (L[i] - 'a' + 1) * P[k][i] % MOD[k]) % MOD[k];
}
}
build_lcp();
FOR(i, 0, m) {
int l, r;
cin >> l >> r;
int ans = 0, mx = l, R = l;
FOR(i, l, r) {
if (R < i)
break;
mx = max(mx, lcp[i]);
if (R == i) {
R = mx;
ans++;
}
}
if (R < r) {
cout << -1 << '\n';
assert(mx < r);
}
else
cout << ans << '\n';
}
}
//13:00:40
