Submission #680244

#	Time	Username	Problem	Language	Result	Execution time	Memory
680244		jhwest2	Tortoise (CEOI21_tortoise)	C++14	0 / 100	1 ms	464 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
                --a[i], 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;
        }

        pq.push(f); sum += f;
        for (int j = 0; j < a[i] - 1; j++)
            pq.push(d), sum += d;

        int x = -1;
        while (!pq.empty() && sum + (i - 1) > 2 * (i - 1)) {
            x = pq.top(); pq.pop();
            sum -= x;
        }
        if (x != -1)
            pq.push(x), sum += x; 
    }

    if (sum + (y - 1) <= 2 * (y - 1))
        --ans;

    cout << ans - (int)pq.size();
    
}

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