Submission #1221333

#	Time	Username	Problem	Language	Result	Execution time	Memory
1221333		im2xtreme	Beech Tree (IOI23_beechtree)	C++20	Compilation error	0 ms	0 KiB

beechtree

#include <iostream>
#include <vector>
#include <unordered_map>
#include "beechtree.h"
using namespace std;

const int MAXN = 200005;

vector<int> tree[MAXN];
int P[MAXN], C[MAXN];
int result[MAXN];

void collect_subtree(int u, vector<int>& nodes) {
    nodes.push_back(u);
    for (int v : tree[u]) {
        collect_subtree(v, nodes);
    }
}

bool is_beautiful(int root) {
    vector<int> nodes;
    collect_subtree(root, nodes);

    if (nodes[0] != root) return false;

    unordered_map<int, int> color_count;

    for (int i = 1; i < (int)nodes.size(); ++i) {
        int curr = nodes[i];
        int color = C[curr];
        int f = color_count[color];

        if (f >= i || P[curr] != nodes[f]) return false;

        color_count[color]++;
    }

    return true;
}

int* beechtree(int N, int M, int* p, int* c) {
    for (int i = 0; i < N; ++i) {
        tree[i].clear();
    }

    for (int i = 1; i < N; ++i) {
        tree[p[i]].push_back(i);
    }

    for (int i = 0; i < N; ++i) {
        P[i] = p[i];
        C[i] = c[i];
    }

    for (int i = 0; i < N; ++i) {
        result[i] = is_beautiful(i) ? 1 : 0;
    }

    return result;
}

Compilation message (stderr)

/usr/bin/ld: /tmp/ccoRSxnq.o: in function `main':
grader.cpp:(.text.startup+0x25d): undefined reference to `beechtree(int, int, std::vector<int, std::allocator<int> >, std::vector<int, std::allocator<int> >)'
collect2: error: ld returned 1 exit status