Cod sursa(job #3234442)

Utilizator hutanuHutanu Andrei hutanu Data 9 iunie 2024 12:39:40
Problema Arbori de intervale Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.27 kb
#include <fstream>
#define NMAX 100002

using namespace std;

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

int n, m, tree[4 * NMAX + 10], tip, a, b;

int interogare(int nod, int left, int right, int st, int dr)
{
    int mij, a1, a2;
    if(st <= left && right <= dr)
        return tree[nod];
    mij = (left + right) / 2;
    a1 = a2 = -2e9;
    if(st <= mij)
        a1 = interogare(2 * nod, left, mij, st, dr);
    if(mij < dr)
        a2 = interogare(2 * nod + 1, mij + 1, right, st, dr);
    return max(a1, a2);
}

void update(int nod, int left, int right, int poz, int val)
{
    int mij;
    if(left == right)
    {
        tree[nod] = val;
        return;
    }
    mij = (left + right) / 2;
    if(poz <= mij)
        update(2 * nod, left, mij, poz, val);
    else
        update(2 * nod + 1, mij + 1, right, poz, val);
    tree[nod] = max(tree[2 * nod], tree[2 * nod + 1]);
}

int main()
{
    int i, x;
    fin >> n >> m;
    for(i = 1; i <= n; i++)
    {
        fin >> x;
        update(1, 1, n, i, x);
    }
    for(i = 1; i <= m; i++)
    {
        fin >> tip >> a >> b;
        if(tip == 0)
            fout << interogare(1, 1, n, a, b) << '\n';
        else
            update(1, 1, n, a, b);
    }
    return 0;
}