Submission #1221334

#	Time	Username	Problem	Language	Result	Execution time	Memory
1221334		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 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(const vector<int>& P, const vector<int>& C, 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, vector<int> P, vector<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) {
        result[i] = is_beautiful(P, C, i) ? 1 : 0;
    }

    return result;
}

Compilation message (stderr)

beechtree.cpp:40:6: error: ambiguating new declaration of 'int* beechtree(int, int, std::vector<int>, std::vector<int>)'
   40 | int* beechtree(int N, int M, vector<int> P, vector<int> C) {
      |      ^~~~~~~~~
In file included from beechtree.cpp:4:
beechtree.h:3:18: note: old declaration 'std::vector<int> beechtree(int, int, std::vector<int>, std::vector<int>)'
    3 | std::vector<int> beechtree(int N, int M, std::vector<int> P, std::vector<int> C);
      |                  ^~~~~~~~~