Submission #397612

#	Time	Username	Problem	Language	Result	Execution time	Memory
397612		MrRobot_28	Index (COCI21_index)	C++17	60 / 110	2593 ms	166428 KiB

index

#include<bits/stdc++.h>
using namespace std;
#define X first
#define Y second
#define int long long
#define sz(a) (int)a.size()
const int mod = 1e9 + 7;
const int N = 2e5;
vector <int> uk_left[N * 4];
vector <int> uk_right[N * 4];
vector <int> Tree[4 * N];
int h[N];
int n, q;
void build(int v, int l, int r)
{
    if(l == r)
    {
        Tree[v].push_back(h[l]);
        return;
    }
    build(v * 2, l, (r + l) / 2);
    build(v * 2 + 1, (r + l) / 2 + 1, r);
    int j = 0;
    for(int i = 0; i < sz(Tree[v * 2]); i++)
    {
        while(j < sz(Tree[v * 2 + 1]) && Tree[v * 2 + 1][j] < Tree[v * 2][i])
        {
            Tree[v].push_back(Tree[v * 2 + 1][j]);
            j++;
        }
        Tree[v].push_back(Tree[v * 2][i]);
    }
    while(j < sz(Tree[v * 2 + 1]))
    {
        Tree[v].push_back(Tree[v * 2 + 1][j]);
        j++;
    }
    int it1 = sz(Tree[v * 2]), it2 = sz(Tree[v * 2 + 1]);
    uk_left[v].resize(r - l + 1);
    uk_right[v].resize(r - l + 1);
    for(int i = sz(Tree[v]) - 1; i >= 0; i--)
    {
        while(it1 > 0 && Tree[v * 2][it1 - 1] >= Tree[v][i])
        {
            it1--;
        }
        uk_left[v][i] = it1;
        while(it2 > 0 && Tree[v * 2 + 1][it2 - 1] >= Tree[v][i])
        {
            it2--;
        }
        uk_right[v][i] = it2;
    }
}
int go_to(int v, int l, int r, int al, int ar, int uk)
{
    if(r < al || l > ar)
    {
        return 0;
    }
    if(uk == sz(Tree[v]))
    {
        return 0;
    }
    if(l >= al && r <= ar)
    {
        return r - l + 1 - uk;
    }
    return go_to(v * 2, l, (r + l) / 2, al, ar, uk_left[v][uk]) + go_to(v * 2 + 1, (r + l) / 2 + 1, r, al, ar, uk_right[v][uk]);
}
int q_ans(int l, int r, int x)
{
    int l1 = -1, r1 = sz(Tree[1]);
    while(r1 - l1 > 1)
    {
        int midd = (r1 + l1) / 2;
        if(Tree[1][midd] < x)
        {
            l1 = midd;
        }
        else
        {
            r1 = midd;
        }
    }
    return go_to(1, 0, n - 1, l, r, r1);
}
signed main()
{
  //  ifstream cin("input1.txt.4c");
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    cin >> n >> q;
    for(int i = 0; i < n; i++)
    {
        cin >> h[i];
    }
    build(1, 0, n - 1);
    while(q--)
    {
        int l, r;
        cin >> l >> r;
        l--;
        r--;
        int l1 = 1, r1 = r - l + 2;
        while(r1 - l1 > 1)
        {
            int midd = (r1 + l1) / 2;
            if(q_ans(l, r, midd) >= midd)
            {
                l1 = midd;
            }
            else
            {
                r1 = midd;
            }
        }
        cout << l1 << "\n";
    }
    return 0;
}

• Subtask 1: 20 / 20
• Subtask 2: 40 / 40
• Subtask 3: 0 / 50