Cod sursa(job #2965128)

Utilizator NathanBBerintan Emanuel Natanael NathanB Data 14 ianuarie 2023 14:53:01
Problema Arbori de intervale Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.12 kb
#include <bits/stdc++.h>

using namespace std;
ifstream fin("arbint.in");
ofstream fout("arbint.out");
vector<int> v;
vector<int> arb;

void update(int nod,int st,int dr,int poz,int val)
{
    if(st==dr)
    {
        arb[nod] = val;
        return;
    }

    int mij = (st+dr)/2;

    if(poz<=mij)
    update(2*nod,st,mij,poz,val);
    else
    update(2*nod+1,mij+1,dr,poz,val);

    arb[nod] = max(arb[2*nod],arb[2*nod+1]);
}

int query(int nod,int st,int dr,int ST,int DR)
{
    if(st>=ST&&dr<=DR)
        return arb[nod];
    int mij = (st+dr)/2;
    int Max = 0;
    if(ST<=mij)
    Max = max(Max,query(2*nod,st,mij,ST,DR));
    if(mij<DR)
    Max = max(Max,query(2*nod+1,mij+1,dr,ST,DR));
    return Max;
}

int main()
{
    int N,M;
    fin>>N>>M;
    v.resize(N+1);
    arb.resize(4*N);
    for(int i = 1 ; i <= N ; ++i)
    {
        fin>>v[i];
        update(1,1,N,i,v[i]);
    }
    for(int i=1;i<=M;++i)
    {
        int x,y,z;
        fin>>x>>y>>z;
        if(x==1)
        update(1,1,N,y,z);
        else
        fout<<query(1,1,N,y,z)<<endl;
    }
    return 0;
}