Submission #1096105

#	Time	Username	Problem	Language	Result	Execution time	Memory
1096105		andrewp	Martian DNA (BOI18_dna)	C++14	100 / 100	26 ms	4692 KiB

dna

//Dedicated to my love, ivaziva
#pragma GCC optimize("Ofast") 
#include <bits/stdc++.h> 
using namespace std;   
 
using pii = pair<int, int>;
using ll = int64_t;  
  
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define pb push_back 
#define dbg(x) cerr<<#x<<": "<<x<<'\n';  
#define dbga(A,l_,r_){for(int i_=l_;i_<=r_;i_++)cerr<<A[i_]<<' ';cerr<<'\n';}
#define dbgv(a_){for(auto x_:a_) cerr<<x_<<' ';cerr<<'\n';}   
 
const int maxn = 2e5 + 3;
int n, k, r;
int a[maxn], info[maxn], f[maxn];

void Add(int x, int& cnt) {
    f[x]++;
    if (f[x] == info[x]) {
        cnt++;
    }
}

void Erase(int x, int& cnt) {
    if (f[x] == info[x]) {
        cnt--;
    }
    f[x]--;
}

int32_t main()  {
    ios::sync_with_stdio(false); cin.tie(nullptr);  
    cout.tie(nullptr); cerr.tie(nullptr);
 
    cin >> n >> k >> r;
    for (int i = 0; i < maxn; i++) {
        info[i] = -1;
    }
    for (int i = 0; i < n; i++) {
        cin >> a[i];
    }
    for (int i = 0; i < r; i++) {
        int B, Q;
        cin >> B >> Q;
        info[B] = Q;
    }
    int cnt = 0;
    int R = -1;
    int ans = maxn;
    for (int i = 0; i < n; i++) {
        while (R + 1 < n && cnt < r) {
            R += 1;
            Add(a[R], cnt);
        }
        if (cnt == r) {
            ans = min(ans, R - i + 1);
        }
        Erase(a[i], cnt);
    }
    if (ans > n) {
        cout << "impossible\n";
        return 0;
    } 
    cout << ans << '\n';
    return 0;   
}

• Subtask 1: 16 / 16
• Subtask 2: 24 / 24
• Subtask 3: 28 / 28
• Subtask 4: 32 / 32