Submission #768522

#	Time	Username	Problem	Language	Result	Execution time	Memory
768522		PurpleCrayon	Distributing Candies (IOI21_candies)	C++17	100 / 100	2041 ms	372964 KiB

candies

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

#define sz(v) int(v.size())
#define ar array
typedef long long ll;
const int N = 2e5+10, MOD = 1e9+7;
const int B = 450, K = N / B + 10;

int n, a[N], cap[N];
vector<int> lzy[K];
vector<pair<int, int>> sorted[K];

int store[N];
void push_block(int block) {
    const auto& v = lzy[block];
    int q = sz(v);
    if (!q) return;

    vector<ll> ps(q);
    for (int i = 0; i < q; i++) {
        ps[i] = v[i];
        if (i) ps[i] += ps[i-1];
    }
 
    vector<ll> mn(q), mx(q);
    for (int i = q-1; i >= 0; i--) {
        mn[i] = mx[i] = ps[i];
        if (i < q-1) mn[i] = min(mn[i], mn[i+1]), mx[i] = max(mx[i], mx[i+1]);
    }
 
    int last = -1;
    for (auto [x, i] : sorted[block]) {
        while (last < q-1) {
            ll cur = (last < 0 || v[last] < 0 ? 0 : x);
            ll cur_ps = last >= 0 ? ps[last] : 0;
            if (mn[last + 1] - cur_ps + cur < 0 || mx[last + 1] - cur_ps + cur >= x) {
                int use = last + 1;
                do {
                    cur += v[use++];
                } while (0 < cur && cur < x);
                last = use - 1;
            } else break;
        }
 
        ll cur = (last < 0 || v[last] < 0 ? 0 : x);
        ll cur_ps = last >= 0 ? ps[last] : 0;
        store[i] = ps.back() - cur_ps + cur;
    }


    ll open = 0;
    ll bound = 0;
    ll lose = 0;
    for (int x : v) {
        open += x;
        if (open < 0) lose += -open;
        open = max(open, 0LL);
        bound = max(bound, open - lose);
    }

    int L = block * B, R = min(n - 1, (block + 1) * B - 1);
    for (int i = L; i <= R; i++) {
        if (bound >= cap[i]) {
            a[i] = store[i];
        } else {
            ll free = min((long long) a[i], cap[i] - bound) - lose;
            a[i] = store[i] + max(0LL, free);
        }
    }

    lzy[block].clear();
}

void op(int i, int x) {
    a[i] += x;
    a[i] = max(a[i], 0);
    a[i] = min(a[i], cap[i]);
}
void upd(int l, int r, int x) {
    int one = l / B, two = r / B;
    if (one == two) {
        push_block(one);
        for (int i = l; i <= r; i++) {
            op(i, x);
        }
    } else {
        push_block(one), push_block(two);
        int one_r = (one + 1) * B - 1;
        int two_l = two * B;
        for (int i = l; i <= one_r; i++) {
            op(i, x);
        }

        for (int i = two_l; i <= r; i++) {
            op(i, x);
        }

        for (int i = one + 1; i < two; i++) {
            lzy[i].push_back(x);
        }
    }
}

vector<int> distribute_candies(vector<int> c, vector<int> l, vector<int> r, vector<int> v) {
    n = sz(c);
    int q = sz(v);
    int k = (n + B - 1) / B;

    for (int i = 0; i < n; i++) cap[i] = c[i];
    for (int i = 0; i < n; i++) {
        sorted[i / B].emplace_back(cap[i], i);
    }
    for (int i = 0; i < k; i++) {
        sort(sorted[i].rbegin(), sorted[i].rend());
    }

    for (int i = 0; i < q; i++) {
        upd(l[i], r[i], v[i]);

        /*
        for (int i = 0; i < n; i++) cerr << a[i] << ' ';
        cerr << endl;
        for (int i = 0; i < k; i++) {
            cerr << "lzy " << i * B << ' ' << (i + 1) * B - 1 << ": ";
            for (int x : lzy[i]) cerr << x << ' ';
            cerr << endl;
        }
        cerr << endl;
        */
    }

    for (int i = 0; i < k; i++) push_block(i);
    return vector<int>(a, a + n);
}

• Subtask 1: 3 / 3
• Subtask 2: 8 / 8
• Subtask 3: 27 / 27
• Subtask 4: 29 / 29
• Subtask 5: 33 / 33