Submission #857349

#	Time	Username	Problem	Language	Result	Execution time	Memory
857349		12345678	Index (COCI21_index)	C++17	110 / 110	392 ms	136740 KiB

index

#include <bits/stdc++.h>

using namespace std;

const int nx=2e5+5;
int n, q, p, l, r;

struct persist
{
    struct node
    {
        int d;
        node *l, *r;
        node(): d(0), l(0), r(0){}
    };
    typedef node* pnode;
    pnode rt[nx];
    void build(int l, int r, pnode &t)
    {
        t=new node();
        if (l==r) return;
        int md=(l+r)/2;
        build(l, md, t->l);
        build(md+1, r, t->r);
    }
    void update(int l, int r, pnode &t, pnode k, int idx)
    {
        t=new node(*k);
        if (l==r) return t->d=k->d+1, void();
        int md=(l+r)/2;
        if (idx<=md) update(l, md, t->l, k->l, idx);
        else update(md+1, r, t->r, k->r, idx);
        t->d=t->l->d+t->r->d;
    }
    int query(int l, int r, pnode pl, pnode pr, int sv)
    {
        //printf("%d %d %d\n", l, r, pr->d-pl->d);
        if (l==r) return l;
        int md=(l+r)/2;
        if (pr->r->d-pl->r->d+sv>=md+1) return query(md+1, r, pl->r, pr->r, sv);
        else return query(l, md, pl->l, pr->l, pr->r->d-pl->r->d+sv);
    }
} s;

int main()
{
    cin.tie(NULL)->sync_with_stdio(false);
    cin>>n>>q;
    s.build(1, nx-1, s.rt[0]);
    for (int i=1; i<=n; i++) cin>>p, s.update(1, nx-1, s.rt[i], s.rt[i-1], p);
    while (q--)
    {
        cin>>l>>r;
        cout<<s.query(1, nx-1, s.rt[l-1], s.rt[r], 0)<<'\n';
    }
}

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