Submission #1219039

#	Time	Username	Problem	Language	Result	Execution time	Memory
1219039		phuonglinhn09	Pilot (NOI19_pilot)	C++20	40 / 100	73 ms	56832 KiB

pilot

/**
 *   author:   phuonglinhn09
 *   created:  17.06.2025
 */

#include <bits/stdc++.h>

using namespace std;

typedef long long ll;

const int nmax = 1e6;

int n, q, a[nmax + 5], ans[nmax + 5];
int h[nmax + 5], y[nmax + 5];
vector<int> vt[nmax + 5], query[nmax + 5];

namespace DSU{
    int par[nmax + 5], sz[nmax + 5];
    ll val[nmax + 5];

    ll get_val(int cnt) {
        ll ans = cnt;
        return ans * (ans - 1) / 2 + ans;
    }

    void preprocess() {
        for (int i = 1; i <= n; i++) {
            par[i] = i;
            val[i] = sz[i] = 1;
        }
    }

    int find_set(int u) {
        return u == par[u] ? u : par[u] = find_set(par[u]);
    }

    ll Union (int u, int v) {
        u = find_set(u);
        v = find_set(v);
        if (u == v) return 0;

        if (sz[v] > sz[u]) swap(u, v);
        par[v] = u, sz[u] += sz[v];

        ll new_val = get_val(sz[u]);
        ll ans = new_val - val[u] - val[v];
        val[u] = val[v] = new_val;
        return ans;
    }
}

int main() {
    ios_base::sync_with_stdio(0); 
    cin.tie(0); cout.tie(0);
    
    if (fopen (".INP", "r")) {
        freopen (".INP", "r", stdin);
        freopen (".OUT", "w", stdout);
    }

    cin >> n >> q;
    for (int i = 1; i <= n; i++) {
        cin >> h[i];
        vt[h[i]].emplace_back(i);
    }
    for (int i = 1; i <= q; i++) {
        cin >> y[i];
        query[y[i]].emplace_back(i);
    }

    sort(h + 1, h + 1 + n);
    sort(y + 1, y + 1 + q);

    DSU::preprocess();
    ll cur_ans = 0;
    int j = 0;

    for (int i = 1; i <= q; i++) {
        if (query[y[i]].empty()) continue;
        
        while (j + 1 <= n && h[j + 1] <= y[i]) {
            j++;
            if (vt[h[j]].empty()) continue;
            
            for (auto idx:vt[h[j]]) {
                a[idx] = h[j];
                cur_ans++;
                if (idx > 1 && a[idx - 1]) cur_ans += DSU::Union(idx, idx - 1);
                if (idx < n && a[idx + 1]) cur_ans += DSU::Union(idx, idx + 1);
            }
            vt[h[j]].clear();
        }

        for (auto pos:query[y[i]]) ans[pos] = cur_ans;
        query[y[i]].clear();
    }

    for (int i = 1; i <= q; i++) {
        cout << ans[i] << "\n";
    }
    
    return 0;
}

Compilation message (stderr)

pilot.cpp: In function 'int main()':
pilot.cpp:58:17: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   58 |         freopen (".INP", "r", stdin);
      |         ~~~~~~~~^~~~~~~~~~~~~~~~~~~~
pilot.cpp:59:17: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   59 |         freopen (".OUT", "w", stdout);
      |         ~~~~~~~~^~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 3 / 3
• Subtask 2: 10 / 10
• Subtask 3: 12 / 12
• Subtask 4: 15 / 15
• Subtask 5: 0 / 5
• Subtask 6: 0 / 9
• Subtask 7: 0 / 14
• Subtask 8: 0 / 10
• Subtask 9: 0 / 11
• Subtask 10: 0 / 11