#include "paint.h"
#include <bits/stdc++.h>
using namespace std;
const int N = 1e5 + 10;
int dp[2][N];
vector<int> pos[N];
bool mark[N];
/*
void input() {
cin >> n >> m >> k;
for (int i = 0; i < n; i++)
cin >> c[i];
for (int i = 0; i < m; i++) {
cin >> a[i];
for (int j = 0; j < a[i]; j++) {
int x;
cin >> x;
b[i].push_back(x);
pos[x].push_back(i);
}
}
}*/
int minimumInstructions(int n, int m, int k, vector<int> c, vector<int> a, vector<vector<int>> b) {
for (int i = 0; i < m; i++)
for (int j: b[i])
pos[j].push_back(i);
vector<int> vec;
for (int i = 0; i < m; i++)
vec.push_back(i);
for (int i = n - 1; i >= 0; i--) {
vector<int> vec2;
for (int j: pos[c[i]]) {
vec2.push_back(j);
dp[i & 1][j] = dp[(i + 1) & 1][(j + 1) % m] + 1;
if (dp[i & 1][j] >= m)
mark[i] = true;
}
for (int j: vec)
dp[(i + 1) & 1][j] = 0;
swap(vec, vec2);
// cout << i << ' ' << mark[i] << '\n';
}
if (!mark[0])
return -1;
int p = m, ans = 1;
while (p < n) {
for (int i = 0; i < m; i++) {
if (p - i >= 0 && mark[p - i]) {
ans++;
p = p - i + m;
break;
}
if (i == m - 1)
return -1;
}
}
return ans;
}
/*
int main() {
ios:: sync_with_stdio(0), cin.tie(0), cout.tie(0);
input();
solve();
}*/
