Submission #1133349

#	Time	Username	Problem	Language	Result	Execution time	Memory
1133349		lopkus	Martian DNA (BOI18_dna)	C++20	100 / 100	77 ms	27972 KiB

dna

#include <bits/stdc++.h>

#define int long long

using namespace std;

signed main() {
    ios::sync_with_stdio(false);
    cin.tie(0);
    int n, dic, r;
    cin >> n >> dic >> r;
    vector<int> a(n + 1);
    for(int i = 1; i <= n; i++) {
        cin >> a[i];
    }
    int ans = n + 1;
    vector<int> p(r + 1);
    vector<int> k(r + 1);
    vector<int> have(n + 1, 0);
    for(int i = 1; i <= r; i++) {
        cin >> p[i] >> k[i];
        have[p[i]] = 1;
    }
    vector<int> pos[n + 1];
    vector<int> some(n + 1, 1e9);
    for(int i = 1; i <= n; i++) {
        pos[a[i]].push_back(i);
    }
    for(int i = 1; i <= r; i++) {
        some[p[i]] = pos[p[i]].size() - 1;
    }
    vector<int> c(n + 1, n + 1);
    set<pair<int,int>> s; // {i + k - 1, a[i]};
    vector<int> cal(n + 1, 0);
    for(int i = 1; i <= r; i++) {
        cal[p[i]] = pos[p[i]].back() + k[i] - 1;
    }
    vector<int> W(n + 1, 0);
    for(int i = 1; i <= r; i++) {
        W[p[i]] = k[i];
    }
    for(int i = n; i >= 1; i--) {
        if(have[a[i]]) {
            int X = cal[a[i]];
            int Y = a[i];
            if(i != n) {
                auto it = s.lower_bound({X, Y});
                if(it != s.end()) {
                    if((*it).first == X && (*it).second == Y) {
                        s.erase(it);
                    }
                }
            }
            if(some[a[i]] + W[a[i]] - 1 >= pos[a[i]].size()) {

            }
            else {
                s.insert({pos[a[i]][some[a[i]] + W[a[i]] - 1], a[i]});
                cal[a[i]] = pos[a[i]][some[a[i]] + W[a[i]] - 1];
            }
            some[a[i]]--;
            if(s.size() < r) {
                continue;
            }
            int d = (*--s.end()).first;
            if(d > n || s.size() < r) {

            }
            else {
                ans = min(ans, d - i + 1);
            }
        }
    }
    if(ans == n + 1) {
        cout << "impossible";
    }
    else {
        cout << ans;
    }
}

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