Submission #1024020

#	Time	Username	Problem	Language	Result	Execution time	Memory
1024020		kustizus	Poklon (COCI17_poklon)	C++17	140 / 140	2197 ms	19636 KiB

poklon

#include <bits/stdc++.h>
using namespace std;
const int N = 5e5;
int n, q, cn, a[N + 5], ans[N + 5];
struct Node
{
    int l, r, pos;
};
vector<Node> qu;
int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    // freopen ("file.inp","r",stdin);
    // freopen ("file.out","w",stdout);
    cin >> n >> q;
    for (int i = 1; i <= n; i++)
        cin >> a[i];
    for (int i = 1; i <= q; i++)
    {
        int l, r;
        cin >> l >> r;
        qu.push_back({l, r, i});
    }
    cn = sqrt(n);
    sort(qu.begin(), qu.end(), [&](Node a, Node b)
         { return a.l / cn < b.l / cn || (a.l / cn == b.l / cn && a.r < b.r); });
    int l = 1, r = 0, now = 0;
    unordered_map<int, int> mp;
    for (int i = 0; i < q; i++)
    {
        while (l < qu[i].l)
        {
            int x = --mp[a[l]];
            if (x == 2)
                now++;
            else if (x == 1)
                now--;
            ++l;
        }
        while (l > qu[i].l)
        {
            --l;
            int x = ++mp[a[l]];
            if (x == 2)
                now++;
            else if (x == 3)
                now--;
        }
        while (r > qu[i].r)
        {
            int x = --mp[a[r]];
            if (x == 2)
                now++;
            else if (x == 1)
                now--;
            r--;
        }
        while (r < qu[i].r)
        {
            r++;
            int x = ++mp[a[r]];
            if (x == 2)
                now++;
            else if (x == 3)
                now--;
        }
        ans[qu[i].pos] = now;
    }
    for (int i = 1; i <= q; i++)
        cout << ans[i] << "\n";
    return 0;
}
// hay

• Subtask 1: 140 / 140