Submission #804725

#	Time	Username	Problem	Language	Result	Execution time	Memory
804725		math_rabbit_1028	Distributing Candies (IOI21_candies)	C++17	8 / 100	1678 ms	36356 KiB

candies

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

struct node {
    ll mx, mn, ly;
} tree[808080];

void propagate(int v, int st, int ed) {
    tree[v].mx += tree[v].ly;
    tree[v].mn += tree[v].ly;
    if (st != ed) {
        tree[2 * v].ly += tree[v].ly;
        tree[2 * v + 1].ly += tree[v].ly;
    }
    tree[v].ly = 0;
}

void update(int v, int st, int ed, int lt, int rt, int val) {
    propagate(v, st, ed);
    if (lt > ed || rt < st) return;
    if (lt <= st && ed <= rt) {
        tree[v].ly += val;
        propagate(v, st, ed);
        return;
    }
    int mid = (st + ed) / 2;
    update(2 * v, st, mid, lt, rt, val);
    update(2 * v + 1, mid + 1, ed, lt, rt, val);
    tree[v].mx = max(tree[2 * v].mx, tree[2 * v + 1].mx);
    tree[v].mn = min(tree[2 * v].mn, tree[2 * v + 1].mn);
}

node get(int v, int st, int ed, int lt, int rt) {
    propagate(v, st, ed);
    if (lt > ed || rt < st) return {(ll)-1e18, (ll)+1e18, 0};
    if (lt <= st && ed <= rt) return tree[v];
    int mid = (st + ed) / 2;
    node lt_val = get(2 * v, st, mid, lt, rt);
    node rt_val = get(2 * v + 1, mid + 1, ed, lt, rt);
    return {max(lt_val.mx, rt_val.mx), min(lt_val.mn, rt_val.mn), 0};
}

std::vector<int> distribute_candies(std::vector<int> C, std::vector<int> l,
                                    std::vector<int> r, std::vector<int> v) {
    int n = C.size();
    int q = l.size();
    
    vector<int> add[202020], rem[202020];
    vector<int> ans(n);

    for (int i = 0; i < q; i++) {
        add[l[i]].push_back(i + 1);
        rem[r[i] + 1].push_back(i + 1);
    }

    for (int i = 0; i < n; i++) {
        for (int j = 0; j < add[i].size(); j++) 
            update(1, 0, q, add[i][j], q, v[add[i][j] - 1]);
        for (int j = 0; j < rem[i].size(); j++)
            update(1, 0, q, rem[i][j], q, -v[rem[i][j] - 1]);

        int st = 0, ed = q;
        while (st < ed) {
            int mid = (st + ed) / 2;
            node prev = get(1, 0, q, mid, q);
            if (prev.mx - prev.mn <= C[i]) ed = mid;
            else st = mid + 1;
        }

        //cout << st << "\n";
        
        if (st == 0) {
            ans[i] = get(1, 0, q, q, q).mx;
            continue;
        }
        if (get(1, 0, q, st, q).mx == get(1, 0, q, st - 1, q).mx) {
            ans[i] = C[i] - get(1, 0, q, st, q).mx + get(1, 0, q, q, q).mx;
            continue;
        }
        if (get(1, 0, q, st, q).mn == get(1, 0, q, st - 1, q).mn) {
            ans[i] = get(1, 0, q, q, q).mx - get(1, 0, q, st, q).mn;
        }
    }

    return ans;
}

Compilation message (stderr)

candies.cpp: In function 'std::vector<int> distribute_candies(std::vector<int>, std::vector<int>, std::vector<int>, std::vector<int>)':
candies.cpp:59:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   59 |         for (int j = 0; j < add[i].size(); j++)
      |                         ~~^~~~~~~~~~~~~~~
candies.cpp:61:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   61 |         for (int j = 0; j < rem[i].size(); j++)
      |                         ~~^~~~~~~~~~~~~~~

• Subtask 1: 0 / 3
• Subtask 2: 8 / 8
• Subtask 3: 0 / 27
• Subtask 4: 0 / 29
• Subtask 5: 0 / 33