Submission #680260

#	Time	Username	Problem	Language	Result	Execution time	Memory
680260		jhwest2	Tortoise (CEOI21_tortoise)	C++17	73 / 100	3079 ms	11316 KiB

tortoise

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

typedef long long ll;
const int N = 505050;

int n, a[N], l[N], r[N], s[N];

int main() {
    cin.tie(0); ios_base::sync_with_stdio(0);
    cin >> n;
    ll ans = 0;
    for (int i = 1; i <= n; i++) {
        cin >> a[i];
        if (a[i] != -1)
            ans += a[i];
    }

    int p = -1, q = -1, y = -1;
    for (int i = 1; i <= n; i++) {
        if (a[i] == -1)
            p = i;
        else {
            if (p != -1)
                l[i] = p;
        }
    }
    p = -1;
    for (int i = n; i >= 1; i--) {
        if (a[i] == -1)
            p = i;
        else if (a[i]) {
            if (p != -1)
                r[i] = p;

            if (q != -1)
                s[i] = q;
            else
                y = i;
            
            q = i;
        }
    }

    priority_queue<int> pq;
    ll sum = 0;
    for (int i = 1; i <= n; i++) {
        if (a[i] <= 0) 
            continue;
        
        int d = 1e9;
        if (l[i])
            d = min(d, 2 * (i - l[i]));
        if (r[i])
            d = min(d, 2 * (r[i] - i));
        
        int f = d;
        if (s[i] && r[i]) {
            if (s[i] < r[i])
                f = min(f, 2 * (r[i] - s[i]));
            else
                f = 0;
        }

        if (i == y)
            f = 0;


        for (int j = 0; j < a[i] - 1; j++) {
            if (sum + (i - 1) > 2 * (i - 1)) {
                if (pq.top() >= d) {
                    sum -= pq.top();
                    pq.pop();
                    sum += d;
                    pq.push(d);
                }
            }
            else {
                sum += d;
                pq.push(d);
            }
        }
        if (sum + (i - 1) > 2 * (i - 1)) {
            if (pq.top() >= f) {
                sum -= pq.top();
                pq.pop();
                sum += f;
                pq.push(f);
            }
        }
        else {
            sum += f;
            pq.push(f); 
        }

        // vector<int> tmp;
        // while (!pq.empty()) {
        //     tmp.push_back(pq.top());
        //     pq.pop();
        // }
        // for (int x : tmp)
        //     cout << x << ' ';
        // cout << '\n';

        // for (int x : tmp)
        //     pq.push(x);
    }
    cout << ans - (int)pq.size();
}

• Subtask 1: 8 / 8
• Subtask 2: 10 / 10
• Subtask 3: 30 / 30
• Subtask 4: 25 / 25
• Subtask 5: 0 / 27