제출 #1199024

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1199024		badge881	Make them Meet (EGOI24_makethemmeet)	C++20	100 / 100	4 ms	840 KiB

Main

#include <bits/stdc++.h>
using namespace std;

class UFD
{
private:
    vector<int> p;

public:
    UFD(int x)
    {
        p.assign(x, 0);
        for (int i = 0; i < x; i++)
            p[i] = i;
    }
    int find(int x) { return (x == p[x]) ? x : p[x] = find(p[x]); }
    bool merge(int a, int b)
    {
        int x = find(a), y = find(b);
        if (x == y)
            return 0;
        p[x] = y;
        return 1;
    }
};

void dfs(int x, int p, vector<vector<int>> &AR, vector<vector<int>> &ans, int &cur, int &last)
{
    if (x != last)
    {
        ans[cur][x] = last;
        cur++;
        last = x;
    }
    for (int i = 0; i < AR[x].size(); i++)
    {
        if (AR[x][i] == p)
            continue;
        dfs(AR[x][i], x, AR, ans, cur, last);
        ans[cur][x] = last;
        cur++;
        last = x;
    }
}
int dfs2(int x, int p, vector<vector<int>> &AR, vector<vector<int>> &ans, int &cur, int depth, int add)
{
    int sub = 1, pos = cur - depth;
    cur += add;
    for (int i = 0; i < AR[x].size(); i++)
    {
        if (AR[x][i] == p)
            continue;
        sub += dfs2(AR[x][i], x, AR, ans, cur, depth + 1, add);
    }
    for (int i = 0; i < sub; i++)
    {
        ans[pos][x] = p;
        pos += add;
    }
    return sub;
}
void dfs3(int x, vector<int> &occ, vector<vector<int>> &AR, int &num, int nono)
{
    num++;
    occ[x] = 1;
    for (int i = 0; i < AR[x].size(); i++)
    {
        if (occ[AR[x][i]])
            continue;
        if (AR[x][i] == nono)
            continue;
        dfs3(AR[x][i], occ, AR, num, nono);
    }
}

int main()
{
    int N, M;
    scanf("%d %d", &N, &M);
    vector<vector<int>> AR(N), AR2(N);
    UFD ufd(N);
    for (int i = 0; i < M; i++)
    {
        int a, b;
        scanf("%d %d", &a, &b);
        AR2[a].push_back(b);
        AR2[b].push_back(a);
    }
    int centre = -1, leaf = -1;
    vector<int> banned(N);
    for (int i = 0; i < N; i++)
    {
        if (centre != -1)
            break;
        for (int j = 0; j < N; j++)
        {
            if (centre != -1)
                break;
            vector<int> temp(N);
            for (int k = 0; k < AR2[i].size(); k++)
                temp[AR2[i][k]] = 1;
            for (int k = 0; k < AR2[j].size(); k++)
                temp[AR2[j][k]] = 0;
            if (temp[j] == 0)
                continue;
            for (int k = 0; k < N; k++)
                if (temp[k] && k != j && k != i)
                    centre = i,
                    leaf = j;
        }
    }

    if (centre == -1)
    {
        int N2 = N;
        if (N % 2 == 0)
            N2++;
        vector<int> perm(N2), C(N2);
        for (int i = 0; i < N2; i++)
        {
            perm[i] = i;
            if (i <= N2 / 2)
            {
                C[i] = i;
                C[N2 - i - 1] = i;
            }
        }
        printf("%d\n", 2 * N2);
        for (int i = 0; i < N2; i++)
        {
            for (int k = 0; k < 2; k++)
            {
                for (int j = 0; j < N; j++)
                    printf("%d ", C[perm[j]]);
                printf("\n");
            }
            swap(perm[0], perm[N2 - 1]);
            for (int j = 1; j < N2 - 1; j++)
                swap(perm[j], perm[j - 1]);
        }
        return 0;
    }
    ufd.merge(centre, leaf);
    AR[centre].push_back(leaf);
    AR[leaf].push_back(centre);
    for (int j = 0; j < AR2[leaf].size(); j++)
        banned[AR2[leaf][j]] = 1;
    for (int i = 0; i < AR2[centre].size(); i++)
    {
        if (AR2[centre][i] == leaf)
            continue;
        if (banned[AR2[centre][i]])
            continue;
        if (ufd.merge(centre, AR2[centre][i]))
        {
            AR[centre].push_back(AR2[centre][i]);
            AR[AR2[centre][i]].push_back(centre);
            for (int j = 0; j < AR2[AR2[centre][i]].size(); j++)
                banned[AR2[AR2[centre][i]][j]] = 1;
        }
    }
    for (int i = 0; i < N; i++)
    {
        if (i == centre)
            continue;
        for (int j = 0; j < AR2[i].size(); j++)
        {
            if (AR2[i][j] == centre)
                continue;
            if (ufd.merge(i, AR2[i][j]))
            {
                AR[i].push_back(AR2[i][j]);
                AR[AR2[i][j]].push_back(i);
            }
        }
    }
    vector<vector<int>> ans(600, vector<int>(N));
    for (int i = 0; i < 600; i++)
        for (int j = 0; j < N; j++)
            ans[i][j] = j;
            
    for (int i = 0; i < 200; i++)
        ans[i * 2][AR[centre][i % 2]] = centre;
    
    for (int i = 0; i < AR[centre].size(); i++)
    {
        int pos = 1;
        if (i == 0)
            pos += 2;
        int temp = dfs2(AR[centre][i], centre, AR, ans, pos, 0, (i <= 1) ? 4 : 2);
    }
    for (int i = 0; i < AR[centre].size(); i++)
        for (int j = 1; j < 400; j += 2)
            ans[j][AR[centre][i]] = centre;

    int cur = 400, last = centre;
    dfs(centre, centre, AR, ans, cur, last);
    printf("600\n");
    for (int i = 0; i < 600; i++)
    {
        for (int j = 0; j < N; j++)
            printf("%d ", ans[i][j]);
        printf("\n");
    }
}

컴파일 시 표준 에러 (stderr) 메시지

Main.cpp: In function 'int main()':
Main.cpp:79:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   79 |     scanf("%d %d", &N, &M);
      |     ~~~~~^~~~~~~~~~~~~~~~~
Main.cpp:85:14: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   85 |         scanf("%d %d", &a, &b);
      |         ~~~~~^~~~~~~~~~~~~~~~~

• Subtask 1: 10 / 10
• Subtask 2: 13 / 13
• Subtask 3: 11 / 11
• Subtask 4: 36 / 36
• Subtask 5: 30 / 30