Submission #1253676

#	Time	Username	Problem	Language	Result	Execution time	Memory
1253676		TheScrasse	Triple Peaks (IOI25_triples)	C++20	11 / 100	26 ms	8116 KiB

triples

#include <bits/stdc++.h>
using namespace std;

#define nl "\n"
#define nf endl
#define ll long long
#define pb push_back
#define _ << ' ' <<

#define INF (ll)1e18
#define mod 998244353
#define maxn 110

#include "triples.h"

long long count_triples(std::vector<int> H) {
    // subtask 4
    ll n = H.size();

    vector<array<ll, 3>> triples;

    auto match = [&](ll i, ll j, ll k) {
        // cout << "match" _ i _ j _ k << nf;
        if (i >= j || j >= k) return;
        array<ll, 3> a = {j - i, k - j, k - i};
        array<ll, 3> b = {H[i], H[j], H[k]};
        sort(a.begin(), a.end());
        sort(b.begin(), b.end());
        if (a == b) triples.pb({i, j, k});
    };

    for (ll k = 0; k < n; k++) {
        ll i = k - H[k];
        if (i < 0) continue;
        ll hj = 2 * k - 2 * i - H[i] - H[k];
        {
            ll j = k - hj;
            match(i, j, k);
        }
        {
            ll j = i + hj;
            match(i, j, k);
        }
    }

    sort(triples.begin(), triples.end());
    triples.resize(unique(triples.begin(), triples.end()) - triples.begin());

    ll ans = triples.size();
    return ans;
}

std::vector<int> construct_range(int M, int K) {
    return {1, 1, 1};
}

• Subtask 0: 0 / 0
• Subtask 1: 0 / 8
• Subtask 2: 0 / 6
• Subtask 3: 0 / 10
• Subtask 4: 11 / 11
• Subtask 5: 0 / 16
• Subtask 6: 0 / 19
• Subtask 7: 0 / 5
• Subtask 8: 0 / 5
• Subtask 9: 0 / 5
• Subtask 10: 0 / 5
• Subtask 11: 0 / 5
• Subtask 12: 0 / 5