Cod sursa(job #3290688)

Utilizator robertcosacCosac Robert-Mihai robertcosac Data 31 martie 2025 16:08:56
Problema Arbori de intervale Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.52 kb
#include <bits/stdc++.h>
using namespace std;
ifstream f("arbint.in");
ofstream g("arbint.out");
int n, aint[400009], v[200009];
void init (int nod, int st, int dr)
{
    if (st==dr) aint[nod]=v[st];
    else
    {
        int mij=(st+dr)/2;
        init (2*nod, st, mij);
        init (2*nod+1, mij+1, dr);
        aint[nod]=max(aint[2*nod], aint[2*nod+1]);
    }
}
void init ()
{
    init (1, 1, n);
}
int query (int nod, int st, int dr, int left, int right)
{
    if (st==left && dr==right) return aint[nod];
    int mij=(st+dr)/2;
    if (right<=mij)
        return query (2*nod, st, mij, left, right);
    if (left>mij)
        return query (2*nod+1, mij+1, dr, left, right);
    return max (query (2*nod, st, mij, left, mij), query (2*nod+1, mij+1, dr, mij+1, right));
}
int query (int a, int b)
{
    return query (1, 1, n, a, b);
}
void update (int nod, int st, int dr, int index, int val)
{
    if (st==dr) aint[nod]=val;
    else
    {
        int mij=(st+dr)/2;
        if (index<=mij)
            update (2*nod, st, mij, index, val);
        else
            update (2*nod+1, mij+1, dr, index, val);
        aint[nod]=max (aint[2*nod], aint[2*nod+1]);
    }
}
void update (int a, int b)
{
    update (1, 1, n, a, b);
}
int main ()
{
    int q;
    f >> n >> q;
    for (int i=1; i<=n; i++)
        f >> v[i];
    init ();
    while (q--)
    {
        int tip, a, b;
        f >> tip >> a >> b;
        if (!tip) g << query (a, b) << '\n';
        else update (a,b);
    }
}