Submission #234701

#	Time	Username	Problem	Language	Result	Execution time	Memory
234701		anonymous	Chameleon's Love (JOI20_chameleon)	C++14	4 / 100	56 ms	512 KiB

chameleon

#include "chameleon.h"
#include <vector>
#include <cassert>
#include <iostream>
#define MAXN 1005
using namespace std;
vector <int> adj[MAXN];
vector <int> M, F;
int Love[MAXN], vis[MAXN];

void findEdge(int i, vector<int> IS) {
    IS.push_back(i);
    if (IS.size() == 1 || Query(IS) == IS.size()) {return;}
    if (IS.size() == 2) {
        adj[i].push_back(IS[0]);
        adj[IS[0]].push_back(i);
    } else {
        IS.pop_back();
        vector <int> L, R;
        int mid = (IS.size() - 1)/2;
        for (int i=0; i < IS.size(); i++) {
            if (i <= mid) {L.push_back(IS[i]);}
            else {R.push_back(IS[i]);}
        }
        findEdge(i, L);
        findEdge(i, R);
    }
}

void dfs(int u, int t, bool c) {
    vis[u] = t;
    if (c) {M.push_back(u);}
    else {F.push_back(u);}
    for (int v: adj[u]) {
        if (vis[v] != t) {dfs(v, t, c^1);}
    }
}

void bipartite(int t) {
    M.clear();
    F.clear();
    for (int i=1; i<t; i++) {
        if (vis[i] != t) {dfs(i,t,0);}
    }
}

void Solve(int N) {
    for (int i=1; i<=2*N; i++) {
        bipartite(i);
        findEdge(i, M);
        findEdge(i, F);
    }
    for (int i=1; i<=2*N; i++) {
        assert(adj[i].size() == 1 || adj[i].size() == 3);
        if (adj[i].size() != 3) {
            if (adj[i][0] > i) {Answer(i, adj[i][0]);}
            continue;
        }
        for (int j=0; j<3; j++) {
            vector <int> Ask;
            Ask.push_back(i);
            for (int k=0; k<3; k++) {
                if (j != k) {Ask.push_back(adj[i][k]);}
            }
            if (Query(Ask) == 1) {
                Love[i] = adj[i][j];
                break;
            }
        }
    }
    bipartite(2*N+1);
    for (int f: F) {
        for (int m: adj[f]) {
            if (Love[m] != f && Love[f] != m && adj[f].size() == 3) {
                Answer(f,m);
            }
        }
    }
}

Compilation message (stderr)

chameleon.cpp: In function 'void findEdge(int, std::vector<int>)':
chameleon.cpp:13:37: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     if (IS.size() == 1 || Query(IS) == IS.size()) {return;}
                           ~~~~~~~~~~^~~~~~~~~~~~
chameleon.cpp:21:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for (int i=0; i < IS.size(); i++) {
                       ~~^~~~~~~~~~~

• Subtask 1: 4 / 4
• Subtask 2: 0 / 20
• Subtask 3: 0 / 20
• Subtask 4: 0 / 20
• Subtask 5: 0 / 36