Submission #537834

#	Time	Username	Problem	Language	Result	Execution time	Memory
537834		N1NT3NDO	Index (COCI21_index)	C++14	110 / 110	792 ms	6372 KiB

index

#include <bits/stdc++.h>
//#include <ext/pb_ds/assoc_container.hpp>
#define ll long long
#define pb push_back
#define sz(x) (int)x.size()
#define fi first
#define sd second
#define all(x) x.begin(), x.end()
//#pragma GCC target ("avx2")
//#pragma GCC optimization ("O3")
//#pragma GCC optimization ("unroll-loops")

using namespace std;
//using namespace __gnu_pbds;

//typedef tree<int, null_type, less<int>, rb_tree_tag, tree_order_statistics_node_update> ordered_set;

const int N = (int)2e5 + 5;
const int M = 400;
int n, a[N], f[N], m, ans[N];

struct que{
    int l, r, idx;
};

bool cmp(const que &a, const que &b)
{
    if (a.l / M != b.l / M)
      return a.l < b.l;
    else return a.r < b.r;
}

void upd(int x, int val)
{
    for(int i = x; i < N; i += i & -i) f[i] += val;
}

int get(int x)
{
    int res = 0;
    for(int i = x; i > 0; i -= i & -i) res += f[i];
    return res;
}

int main()
{
    ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
    cin >> n >> m;
    for(int i = 1; i <= n; i++) cin >> a[i];
    vector< que > queries;
    for(int i = 1; i <= m; i++)
    {
        int l, r;
        cin >> l >> r;
        queries.pb({l, r, i});
    }

    sort(all(queries), cmp);

    int cur_l = 1, cur_r = 0;

    for(const auto &[l, r, nom] : queries)
    {
        while(cur_l > l)
        {
            cur_l--;
            upd(a[cur_l], 1);
        }

        while(cur_r < r)
        {
            cur_r++;
            upd(a[cur_r], 1);
        }

        while(cur_l < l)
        {
            upd(a[cur_l], -1);
            cur_l++;
        }

        while(cur_r > r)
        {
            upd(a[cur_r], -1);
            cur_r--;
        }

        int L = 1, R = r - l + 1;
        while(L < R)
        {
            int m = (L + R + 1) >> 1;
            if (get(N - 1) - get(m - 1) >= m) L = m;
            else R = m - 1;
        }

        ans[nom] = L;
    }

    for(int i = 1; i <= m; i++) cout << ans[i] << '\n';
}

Compilation message (stderr)

index.cpp: In function 'int main()':
index.cpp:62:21: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   62 |     for(const auto &[l, r, nom] : queries)
      |                     ^

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