Cod sursa(job #2711952)

Utilizator vladadAndries Vlad Andrei vladad Data 24 februarie 2021 22:00:41
Problema Arbori de intervale Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.33 kb
#include<bits/stdc++.h>
#define fi first
#define sc second
#define ll long long
using namespace std;
ifstream f("arbint.in");
ofstream g("arbint.out");
int n, q, v[400001], aint[800001], op;
void build(int nod, int st, int dr)
{
    if(st==dr)
    {
        aint[nod]=v[st];
        return;
    }
    int mid=(st+dr)/2;
    build(nod*2, st, mid);
    build(nod*2+1, mid+1, dr);
    aint[nod]=max(aint[nod*2], aint[nod*2+1]);
}
int query(int nod, int st, int dr, int l, int r)
{
    int A, B;
    if(r<st || l>dr)
        return 0;
    if(l<=st && r>=dr)
        return aint[nod];
    int mid=(st+dr)/2;
    A=query(nod*2, st, mid, l, r);
    B=query(nod*2+1, mid+1, dr, l, r);
    return max(A, B);
}
void update(int nod, int st, int dr, int poz, int val)
{
    if(st==dr)
    {
        aint[nod]=val;
        return;
    }
    int mid=(st+dr)/2;
    if(poz<=mid)
        update(nod*2, st, mid, poz, val);
    else
        update(nod*2+1, mid+1, dr, poz, val);
    aint[nod]=max(aint[nod*2], aint[nod*2+1]);
}
int main()
{
    f>>n>>q;
    for(int i=1; i<=n; i++)
        f>>v[i];
    build(1, 1, n);
    for(; q; q--)
    {
        int a, b;
        f>>op>>a>>b;
        if(op==0)
            g<<query(1, 1, n, a, b)<<'\n';
        else
            update(1, 1, n, a, b);
    }
    return 0;
}