Submission #568289

#	Time	Username	Problem	Language	Result	Execution time	Memory
568289		abc864197532	Chameleon's Love (JOI20_chameleon)	C++17	64 / 100	52 ms	472 KiB

chameleon

#include <bits/stdc++.h>
using namespace std;
#define lli long long int
#define mp make_pair
#define pb push_back
#define eb emplace_back
#define pii pair <int, int>
#define X first
#define Y second
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
void abc() {cout << endl;}
template <typename T, typename ...U> void abc(T a, U ...b) {
    cout << a << ' ', abc(b...);
}
template <typename T> void printv(T l, T r) {
    for (; l != r; ++l) cout << *l << " \n"[l + 1 == r];
}
template <typename A, typename B> istream& operator >> (istream& o, pair<A, B> &a) {
    return o >> a.X >> a.Y;
}
template <typename A, typename B> ostream& operator << (ostream& o, pair<A, B> a) {
    return o << '(' << a.X << ", " << a.Y << ')';
}
template <typename T> ostream& operator << (ostream& o, vector<T> a) {
    bool is = false;
    if (a.empty()) return o << "{}";
    for (T i : a) {o << (is ? ' ' : '{'), is = true, o << i;}
    return o << '}';
}
template <typename T> struct vv : vector <vector <T>> {
    vv(int n, int m, T v) : vector <vector <T>> (n, vector <T>(m, v)) {}
    vv() {}
};
template <typename T> struct vvv : vector <vv <T>> {
    vvv(int n, int m, int k, T v) : vector <vv <T>> (n, vv <T>(m, k, v)) {}
    vvv() {}
};
#ifdef Doludu
#define test(args...) abc("[" + string(#args) + "]", args)
#define owo freopen("input.txt", "r", stdin), freopen("output.txt", "w", stdout);
#include "grader.cpp"
#else
#define test(args...) void(0)
#define owo ios::sync_with_stdio(false); cin.tie(0)
#include "chameleon.h"
#endif
const int mod = 1e9 + 7, N = 100000, logN = 20, K = 48763;

void Solve(int n) {
    vector <vector <int>> g(n * 2 + 1), adj(n * 2 + 1);
    vector <int> rem;
    for (int i = 1; i <= 2 * n; ++i) {
        rem.pb(i);
    }
    while (!rem.empty()) {
        vector <int> left, right;
        for (int i : rem) {
            left.pb(i);
            int nxt = Query(left);
            left.pop_back();
            if (nxt == left.size() + 1)
                left.pb(i);
            else
                right.pb(i);
        }
        for (int i = 0; i < right.size(); ++i) {
            int l = 0;
            while (true) {
                int r = left.size();
                {
                    vector <int> now;
                    for (int i = l; i < r; ++i) 
                        now.pb(left[i]);
                    int x = Query(now);
                    now.pb(right[i]);
                    int y = Query(now);
                    if (y > r - l)
                        break;
                }
                while (r - l > 1) {
                    int m = l + r >> 1;
                    vector <int> now;
                    for (int i = l; i < m; ++i)
                        now.pb(left[i]);
                    now.pb(right[i]);
                    int y = Query(now);
                    if (y <= m - l)
                        r = m;
                    else
                        l = m;
                }
                test(left[l], right[i]);
                g[left[l]].pb(right[i]), g[right[i]].pb(left[l]), l++;
            }
        }
        rem = right;
    }
    vector <int> pr(n * 2 + 1);
    for (int i = 1; i <= n * 2; ++i) {
        if (g[i].size() == 2) {
            adj[i] = g[i];
        } else if (g[i].size() == 3) {
            if (Query({i, g[i][0], g[i][1]}) == 1)
                adj[i].pb(g[i][2]);
            else if (Query({i, g[i][0], g[i][2]}) == 1)
                adj[i].pb(g[i][1]);
            else 
                adj[i].pb(g[i][0]);
        } else {
            pr[i] = g[i][0];
        }
    }
    vector <bool> vis_dfs(n * 2 + 1, false);
    vector <int> cyc;
    function <void(int)> dfs = [&](int v) {
        vis_dfs[v] = true;
        cyc.pb(v);
        for (int u : adj[v]) if (!vis_dfs[u])
            dfs(u);
    };
    vector <bool> vis(n * 2 + 1, false);
    for (int i = 1; i <= n * 2; ++i) if (!vis_dfs[i]) {
        int st = i;
        cyc.clear(), dfs(st);
        // check pair in the same cycle
        int m = cyc.size();
        for (int j = 0; j < m; ++j) if (g[cyc[j]].size() == 3) {
            vector <int> now = g[cyc[j]];
            {
                auto it = find(all(now), cyc[(j + 1) % m]);
                assert(it != now.end());
                now.erase(it);
            }
            {
                auto it = find(all(now), cyc[(j + m - 1) % m]);
                assert(it != now.end());
                now.erase(it);
            }
            pr[cyc[j]] = now[0];
        }
    }
    for (int i = 1; i <= 2 * n; ++i) {
        assert(pr[pr[i]] == i);
        if (i < pr[i])
            Answer(i, pr[i]);
    }
}

Compilation message (stderr)

chameleon.cpp: In function 'void Solve(int)':
chameleon.cpp:63:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   63 |             if (nxt == left.size() + 1)
      |                 ~~~~^~~~~~~~~~~~~~~~~~
chameleon.cpp:68:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   68 |         for (int i = 0; i < right.size(); ++i) {
      |                         ~~^~~~~~~~~~~~~~
chameleon.cpp:76:25: warning: unused variable 'x' [-Wunused-variable]
   76 |                     int x = Query(now);
      |                         ^
chameleon.cpp:83:31: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   83 |                     int m = l + r >> 1;
      |                             ~~^~~

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