Cod sursa(job #2835231)

Utilizator toma_ariciuAriciu Toma toma_ariciu Data 18 ianuarie 2022 12:14:18
Problema Arbori de intervale Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.25 kb
#include <fstream>

using namespace std;

ifstream fin("arbint.in");
ofstream fout("arbint.out");

int arbint[400005], maxi, n, q;

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

void query(int nod, int st, int dr, int a, int b)
{
    if(a <= st && dr <= b)
    {
        maxi = max(maxi, arbint[nod]);
        return;
    }
    int med = (st + dr) / 2;
    if(a <= med)
        query(2 * nod, st, med, a, b);
    if(med + 1 <= b)
        query(2 * nod + 1, med + 1, dr, a, b);
}

int main()
{
    fin >> n >> q;
    for(int i = 1; i <= n; i++)
    {
        int x;
        fin >> x;
        update(1, 1, n, i, x);
    }
    for(int i = 1; i <= q; i++)
    {
        int op, x, y;
        maxi = -1;
        fin >> op >> x >> y;
        if(op == 0)
        {
            query(1, 1, n, x, y);
            fout << maxi << '\n';
        }
        if(op == 1)
            update(1, 1, n, x, y);
    }
    return 0;
}