Submission #1297764

#	Time	Username	Problem	Language	Result	Execution time	Memory
1297764		chikien2009	Event Hopping 2 (JOI21_event2)	C++20	1 / 100	1 ms	576 KiB

event2

#include <bits/stdc++.h>

using namespace std;

void setup()
{
#ifndef ONLINE_JUDGE
    freopen("test.inp", "r", stdin);
    freopen("test.out", "w", stdout);
#endif
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
}

int n, k;
pair<int, int> p[20];
bool cut[20][20];

inline void Form(int ind, int num, int bit)
{
    bool check = true;
    if (num == k)
    {
        for (int i = 0; i < n; ++i)
        {
            if ((bit >> i) & 1)
            {
                cout << i + 1 << "\n";
            }
        }
        exit(0);
    }
    if (num + n - ind < k)
    {
        return;
    }
    for (int i = 0; i < n; ++i)
    {
        if (ind != i && ((bit >> i) & 1) && cut[ind][i])
        {
            check = false;
            break;
        }
    }
    if (check)
    {
        Form(ind + 1, num + 1, bit + (1 << ind));
    }
    Form(ind + 1, num, bit);
}

int main()
{
    // setup();

    cin >> n >> k;
    for (int i = 0; i < n; ++i)
    {
        cin >> p[i].first >> p[i].second;
    }
    for (int i = 0; i < n; ++i)
    {
        for (int j = 0; j < n; ++j)
        {
            cut[i][j] = !((p[i].second <= p[j].first || p[j].second <= p[i].first));
        }
    }
    Form(0, 0, 0);
    cout << -1;
    return 0;
}

Compilation message (stderr)

event2.cpp: In function 'void setup()':
event2.cpp:8:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
    8 |     freopen("test.inp", "r", stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
event2.cpp:9:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
    9 |     freopen("test.out", "w", stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 0 / 7
• Subtask 2: 1 / 1
• Subtask 3: 0 / 31
• Subtask 4: 0 / 61