#include <bits/stdc++.h>
#pragma GCC optimize("Ofast,no-stack-protector,unroll-loops,fast-math,O3")
#pragma GCC optimize("Ofast")
#pragma GCC target("avx,avx2,fma")
#pragma GCC optimization("unroll-loops")
#pragma ("reroll")
#define skip continue;
#define gold ios_base::sync_with_stdio(false);cin.tie(NULL);
#define xa "\n"
#define int long long
#define all(a) a.begin(), a.end()
#define pb push_back
#define F first
#define S second
using namespace std;
const int mod = 1e9 + 7;
const int N = 4e3 + 7;
const int MAX = 1e9;
const int inf = 1e18;
int gcd(int a, int b) { if (b == 0) return a; else if(a == 0) return b; else return gcd(b, a % b); }
int lcm(int a, int b) { return a / gcd(a, b) * b; }
int pref[N][N];
void solve() {
    int n, k, q;
    cin >> n >> k >> q;
    int a[n + 1];
    int fr[q + 1], sc[q + 1];
    for(int i = 1; i <= n; i++){
        cin >> a[i];
        for(int j = 0; j <= k; j++){
            pref[j][i] = pref[j][i - 1];
        }
        pref[a[i]][i]++;
    }
    for(int i = 1; i <= q; i++){
        cin >> fr[i] >> sc[i];
    }
    int ok = 1;
    for(int i = 1; i <= q; i++){
        if(pref[fr[i]][n] - pref[fr[i]][0] < sc[i]) ok = 0;
    }
    if(!ok){
        cout << "impossible";
        return;
    }
    int mn = inf;
    for(int l = 1; l <= n; l++){
        for(int r = l; r <= n; r++){
            ok = 1;
            for(int i = 1; i <= q; i++){
                if(pref[fr[i]][r] - pref[fr[i]][l - 1] < sc[i]) ok = 0;
            }
            if(ok) mn = min(mn, r - l + 1);
        }
    }
    cout << mn;
}
signed main() {
    gold;
    //freopen("rmq.in", "r", stdin);
    //freopen("rmq.out", "w", stdout);
    int t = 1;
    int ti = 1;
    //cin >> t;
    while (t--) {
        //cout << "Case " << ti << ": ";
        solve();
        ti++;
    }
}
| # | Verdict | Execution time | Memory | Grader output | 
|---|
| Fetching results... | 
| # | Verdict | Execution time | Memory | Grader output | 
|---|
| Fetching results... | 
| # | Verdict | Execution time | Memory | Grader output | 
|---|
| Fetching results... | 
| # | Verdict | Execution time | Memory | Grader output | 
|---|
| Fetching results... |