Submission #1194726

#	Time	Username	Problem	Language	Result	Execution time	Memory
1194726		DeathIsAwe	Infinite Race (EGOI24_infiniterace2)	C++20	100 / 100	105 ms	18388 KiB

Main

#include <bits/stdc++.h>
#define pb push_back
#define mp make_pair
#define ff first
#define ss second
#define ll long long
using namespace std;


int main() {
    int n, q; cin >> n >> q;
    int query, ans = 0;
    unordered_set<int> behind, infront;
    for (int i=1;i<n;i++) {
        infront.insert(i);
    }
    for (int i=0;i<q;i++) {
        cin >> query;
        if (query < 0) {
            query = -query;
            if (behind.find(query) != behind.end()) {
                behind.erase(query);
                infront.insert(query);
            }
        } else {
            if (behind.find(query) != behind.end()) {
                for (int j: behind) {
                    if (j == query) continue;
                    infront.insert(j);
                }
                behind.clear();
                behind.insert(query);
                ans += 1;
            } else {
                infront.erase(query);
                behind.insert(query);
            }
        }
    }


    cout << ans;
}

• Subtask 1: 29 / 29
• Subtask 2: 34 / 34
• Subtask 3: 22 / 22
• Subtask 4: 15 / 15