Submission #235462

#	Time	Username	Problem	Language	Result	Execution time	Memory
235462		anonymous	Chameleon's Love (JOI20_chameleon)	C++14	100 / 100	52 ms	512 KiB

chameleon

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

bool findEdge(int i, vector<int> IS, bool b) {
    IS.push_back(i);
    if (Num == 3 || IS.size() == 1 || (!b && Query(IS) == IS.size())) {return(false);}
    if (IS.size() == 2) {
        adj[i].push_back(IS[0]);
        adj[IS[0]].push_back(i);
        Num++;
        return(true);
    } 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]);}
        }
        if (!findEdge(i, L, 0)) {
            findEdge(i, R, 1);
        } else {
            findEdge(i, R, 0);
        }
        return(true);
    }
}

void dfs(int u, int t, bool c, bool k) {
    vis[u] = t;
    if (c && (adj[u].size() != 3 || k)) {M.push_back(u);}
    else if (adj[u].size() != 3 || k) {F.push_back(u);}
    for (int v: adj[u]) {
        if (vis[v] != t) {dfs(v, t, c^1,k);}
    }
}

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

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

Compilation message (stderr)

chameleon.cpp: In function 'bool findEdge(int, std::vector<int>, bool)':
chameleon.cpp:11:56: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     if (Num == 3 || IS.size() == 1 || (!b && Query(IS) == IS.size())) {return(false);}
                                              ~~~~~~~~~~^~~~~~~~~~~~
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: 20 / 20
• Subtask 3: 20 / 20
• Subtask 4: 20 / 20
• Subtask 5: 36 / 36