Cod sursa(job #3287848)

Utilizator tudor_costinCostin Tudor tudor_costin Data 19 martie 2025 15:41:54
Problema Arbori de intervale Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.34 kb
#include <bits/stdc++.h>

using namespace std;
ifstream fin("arbint.in");
ofstream fout("arbint.out");
struct node
{
    node* st;
    node* dr;
    int val;
    node()
    {
        st=nullptr;
        dr=nullptr;
        val=0;
    }
};
void update(node* nod,int l,int r,int poz,int x)
{
    if(l==r)
    {
        nod->val=x;
        return;
    }
    int mid=(l+r)/2;
    if(!nod->st) nod->st=new node;
    if(!nod->dr) nod->dr=new node;
    if(poz<=mid) update(nod->st,l,mid,poz,x);
    else update(nod->dr,mid+1,r,poz,x);
    nod->val=max(nod->st->val,nod->dr->val);
    return;
}
int query(node* nod,int l,int r,int st,int dr)
{
    if(st<=l && r<=dr)
    {
        return nod->val;
    }
    int mid=(l+r)/2;
    if(!nod->st) nod->st=new node;
    if(!nod->dr) nod->dr=new node;
    if(dr<=mid) return query(nod->st,l,mid,st,dr);
    if(mid<st) return query(nod->dr,mid+1,r,st,dr);
    return max(query(nod->st,l,mid,st,mid),query(nod->dr,mid+1,r,mid+1,dr));
}
node* root=new node;
int main()
{
    int n,m;
    fin>>n>>m;
    for(int i=1;i<=n;i++)
    {
        int x;
        fin>>x;
        update(root,1,n,i,x);
    }
    for(int i=1;i<=m;i++)
    {
        int c,a,b;
        fin>>c>>a>>b;
        if(c==0) fout<<query(root,1,n,a,b)<<'\n';
        else update(root,1,n,a,b);
    }
    return 0;
}