Submission #398654

#	Time	Username	Problem	Language	Result	Execution time	Memory
398654		4fecta	Event Hopping 2 (JOI21_event2)	C++17	32 / 100	351 ms	2428 KiB

event2

#include <bits/stdc++.h>

using namespace std;
#define ll long long
#define int ll
#define ld long double
#define pii pair<int, int>
#define f first
#define s second
#define boost() cin.tie(0), cin.sync_with_stdio(0)

bool cmp(pii p, pii q) {
    return p.s < q.s;
}

const int MN = 6005;

int n, k, vis[MN], dp1[MN], dp2[MN];
pii a[MN];
vector<int> xs, ls[MN], rs[MN];
map<int, int> mp;

int32_t main() {
    boost();

    cin >> n >> k;
    for (int i = 1; i <= n; i++) {
        cin >> a[i].f >> a[i].s;
        xs.push_back(a[i].f);
        xs.push_back(a[i].s);
    }
    sort(xs.begin(), xs.end());
    xs.erase(unique(xs.begin(), xs.end()), xs.end());
    for (int i = 0; i < xs.size(); i++) mp[xs[i]] = i + 1;
    for (int i = 1; i <= n; i++) a[i].f = mp[a[i].f], a[i].s = mp[a[i].s];
    vector<int> out;
    for (int c = 1; c <= k; c++) {
        for (int i = 1; i <= xs.size(); i++) ls[i].clear(), rs[i].clear();
        vector<pii > v;
        for (int i = 1; i <= n; i++) {
            if (vis[i]) continue;
            ls[a[i].s].push_back(a[i].f);
            rs[a[i].f].push_back(a[i].s);
        }
        memset(dp1, 0, sizeof(dp1));
        memset(dp2, 0, sizeof(dp2));
        for (int i = 1; i <= xs.size(); i++) {
            dp1[i] = dp1[i - 1];
            for (int p : ls[i]) dp1[i] = max(dp1[i], dp1[p] + 1);
        }
        for (int i = xs.size(); i > 0; i--) {
            dp2[i] = dp2[i + 1];
            for (int p : rs[i]) dp2[i] = max(dp2[i], dp2[p] + 1);
        }
        for (int i = 1; i <= n; i++) {
            if (vis[i]) continue;
            if (dp1[a[i].f] + dp2[a[i].s] >= k - c) {
                vis[i] = 1;
                for (int j = 1; j <= n; j++) {
                    if (a[j].f >= a[i].s || a[j].s <= a[i].f) continue;
                    vis[j] = 1;
                }
                out.push_back(i);
                break;
            }
        }
        if (out.size() < c) return 0 * printf("-1\n");
    }
    for (int p : out) printf("%lld\n", p);

    return 0;
}

Compilation message (stderr)

event2.cpp: In function 'int32_t main()':
event2.cpp:34:23: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   34 |     for (int i = 0; i < xs.size(); i++) mp[xs[i]] = i + 1;
      |                     ~~^~~~~~~~~~~
event2.cpp:38:27: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   38 |         for (int i = 1; i <= xs.size(); i++) ls[i].clear(), rs[i].clear();
      |                         ~~^~~~~~~~~~~~
event2.cpp:47:27: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   47 |         for (int i = 1; i <= xs.size(); i++) {
      |                         ~~^~~~~~~~~~~~
event2.cpp:67:24: warning: comparison of integer expressions of different signedness: 'std::vector<long long int>::size_type' {aka 'long unsigned int'} and 'long long int' [-Wsign-compare]
   67 |         if (out.size() < c) return 0 * printf("-1\n");
      |             ~~~~~~~~~~~^~~

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