Submission #1249840

#	Time	Username	Problem	Language	Result	Execution time	Memory
1249840		kduckp	Triple Peaks (IOI25_triples)	C++20	14.17 / 100	2093 ms	1972 KiB

triples

#include "triples.h"
#include <vector>
#include <algorithm>
using namespace std;

long long count_triples(vector<int> H) {
    int n = H.size();
    long long res = 0;

    if (n <= 2000) {
        for (int i = 0; i < n; ++i)
            for (int j = i + 1; j < n; ++j)
                for (int k = j + 1; k < n; ++k) {
                    vector<int> h = {H[i], H[j], H[k]};
                    vector<int> d = {j - i, k - i, k - j};
                    sort(h.begin(), h.end());
                    sort(d.begin(), d.end());
                    if (h == d) res++;
                }
        return res;
    }

    // Tối ưu với small_value: mọi H[i] <= 10
    bool small_value = true;
    for (int h : H)
        if (h > 10) {
            small_value = false;
            break;
        }

    if (small_value) {
        for (int i = 0; i < n; ++i)
            for (int j = i + 1; j < min(n, i + 11); ++j)
                for (int k = j + 1; k < min(n, i + 22); ++k) {
                    vector<int> h = {H[i], H[j], H[k]};
                    vector<int> d = {j - i, k - i, k - j};
                    sort(h.begin(), h.end());
                    sort(d.begin(), d.end());
                    if (h == d) res++;
                }
        return res;
    }

    return 0;
}


vector<int> construct_range(int M, int K) {
    return {1, 1, 2};
}

• Subtask 0: 0 / 0
• Subtask 1: 8 / 8
• Subtask 2: 6 / 6
• Subtask 3: 0 / 10
• Subtask 4: 0 / 11
• Subtask 5: 0 / 16
• Subtask 6: 0 / 19
• Subtask 7: 0.1667 / 5
• Subtask 8: 0.0025 / 5
• Subtask 9: 0.0001 / 5
• Subtask 10: 0 / 5
• Subtask 11: 0 / 5
• Subtask 12: 0 / 5