Cod sursa(job #2188977)

Utilizator Te_pup_dulce_nu_plecaClorina Intergalactica Valoroasa Te_pup_dulce_nu_pleca Data 27 martie 2018 16:41:05
Problema Arbori de intervale Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.24 kb
#include <bits/stdc++.h>
#define nmax 100001
using namespace std;
ifstream fin("arbint.in");
ofstream fout("arbint.out");
long int n,m;
long int aint[4*nmax];

void update(long int nod,long int st,long int dr,long int poz,long int val)
{
    if(st==dr)
        aint[nod]=val;
    else
    {
        int mijl=(st+dr)/2;
        if(poz<=mijl)
            update(nod*2,st,mijl,poz,val);
            else
                update(nod*2+1,mijl+1,dr,poz,val);
        aint[nod]=max(aint[nod*2],aint[nod*2+1]);
    }
}

long int mx;

void query(long int nod,long int st,long int dr,long int a,long int b)
{
    if(a<=st && dr<=b)
        mx=max(mx,aint[nod]);
    else
    {
        int mijl=(st+dr)/2;
        if(a<=mijl)
            query(nod*2,st,mijl,a,b);
        if(b>mijl)
            query(nod*2+1,mijl+1,dr,a,b);
    }
}

int main()
{
    fin>>n>>m;
    for(long int i=1;i<=n;i++)
    {
        int x;
        fin>>x;
        update(1,1,n,i,x);
    }

    for(long int i=1;i<=m;i++)
    {
        int p,a,b;
        fin>>p>>a>>b;
        if(p==1)
        update(1,1,n,a,b);
        else
        {
            mx=0;
            query(1,1,n,a,b);
            fout<<mx<<'\n';
        }
    }

    return 0;
}