#include <bits/stdc++.h>
using namespace std;
int minimumInstructions(
int N, int M, int K, std::vector<int> C,
std::vector<int> A, std::vector<std::vector<int>> B) {
vector<bool> pos(N);
vector<vector<int>> f(K + 1);
for (int i = 0; i < M; ++i) {
for (auto x: B[i]) {
f[x].push_back(i);
}
}
vector<int> app(max(K + 1, M + 1));
int amountK = 0;
for (int i = 0; i < N; ++i) {
for (auto x : f[C[i]]) {
int v = x - i;
while (v < 0) v += M;
if (app[v] == M) amountK--;
app[v]++;
if (app[v] == M) amountK++;
}
if (i - M >= 0) {
for (auto x : f[C[i -M]]) {
int v = x - (i - M);
while (v < 0) v += M;
if (app[v] == M) amountK--;
app[v]--;
if (app[v] == M) amountK++;
}
}
if (amountK > 0 && i - M + 1 >= 0)
pos[i - M + 1] = true;
}
int ans = 0;
int x = 0;
int prev = 0;
while (x < N) {
if (pos[x]) {
ans++;
x += M;
prev = x;
}
else x--;
if (x < 0) {
return -1;
} else if (prev - M >= x) return -1;
if (ans > N) return -1;
}
return ans;
}
#if DEBUG
int main() {
int N, M, K;
assert(3 == scanf("%d %d %d", &N, &M, &K));
std::vector<int> C(N);
for (int i = 0; i < N; ++i) {
assert(1 == scanf("%d", &C[i]));
}
std::vector<int> A(M);
std::vector<std::vector<int>> B(M);
for (int i = 0; i < M; ++i) {
assert(1 == scanf("%d", &A[i]));
B[i].resize(A[i]);
for (int j = 0; j < A[i]; ++j) {
assert(1 == scanf("%d", &B[i][j]));
}
}
int minimum_instructions = minimumInstructions(N, M, K, C, A, B);
printf("%d\n", minimum_instructions);
return 0;
}
#endif
