Submission #1250579

#	Time	Username	Problem	Language	Result	Execution time	Memory
1250579		s4dz	Triple Peaks (IOI25_triples)	C++20	Compilation error	0 ms	0 KiB

triples

#include <bits/stdc++.h>
using namespace std;
using ll = long long;
//sub4:
#define int long long
std::vector<int> construct_range(int M, int K)
{
    return{};
}
/*long long count_triples(vector<int> H)
{
    int n = H.size();
    ll ans = 0;
    for (int k = 0; k < n; k++)
    {
        int c = H[k];
        int i = k - c;
        if (i < 0 || i >= n) continue;

        int a = H[i];
        if (a > c - a) continue;

        int need = c - a;
        int j1   = i + a;
        int j2   = k - a;
        if (i < j1 && j1 < k && H[j1] == need) ans++;
        if (j2 != j1 && i < j2 && j2 < k && H[j2] == need) ans++;
    }
    return ans;
}*/

long long count_triples(vector<int> H)
{
    int n = H.size();
    long long ans = 0;
    for (int i = 0; i < n; i++)
    {
        int k = i + H[i];
        if (k >= n) continue;
        int d = H[k];
        int j1 = i + d;
        int j2 = k - d;
        if (j1 == j2)
        {
            if (i < j1 && j1 < k)
            {
                if (H[j1] == k - j1) ans++;
            }
        }
        else
        {
            if (i < j1 && j1 < k)
            {
                if (H[j1] == k - j1) ans++;
            }
            if (i < j2 && j2 < k)
            {
                if (H[j2] == j2 - i) ans++;
            }
        }
    }
    for (int k = 0; k < n; k++)
    {
        int i = k - H[k];
        int d = H[i];
        int j1 = i + d;
        int j2 = k - d;
        if (j1 == j2)
        {
            if (i < j1 && j1 < k)
            {
                if (H[j1] == k - j1) ans++;
            }
        }
        else
        {
            if (i < j1 && j1 < k)
            {
                if (H[j1] == k - j1) ans++;
            }
            if (i < j2 && j2 < k)
            {
                if (H[j2] == j2 - i) ans++;
            }
        }
    }
    for (int i = 0; i < n; i++)
    {
        int j = i + H[i];
        if (j >= n) continue;
        int k = i + H[j];
        if (k >= n) continue;
        if (k > j && H[k] == k - j) ans++;
    }

    unordered_map<int, vector<int>> nhom;
    for (int i = 0; i < n; i++)
    {
        int x = H[i] - i;
        nhom[x].push_back(i);
    }

    for (auto &p : nhom)
    {
        int x = p.first;
        vector<int> A = p.second;
        sort(A.begin(), A.end());
        for (int u = 0; u < A.size(); u++)
        {
            int i = A[u];
            for (int v = u + 1; v < A.size(); v++)
            {
                int j = A[v];
                int k = i + j + x;
                if (k >= n) break;
                if (H[i] == j - i) continue;
                if (H[k] == j - i) ans++;
            }
        }
    }
    return ans;
}

Compilation message (stderr)

/usr/bin/ld: /tmp/ccrOidjE.o: in function `main':
grader.cpp:(.text.startup+0x18a): undefined reference to `construct_range(int, int)'
/usr/bin/ld: grader.cpp:(.text.startup+0x37b): undefined reference to `count_triples(std::vector<int, std::allocator<int> >)'
collect2: error: ld returned 1 exit status