Cod sursa(job #3003251)

Utilizator GabiRB1Rafael GabiRB1 Data 15 martie 2023 17:03:51
Problema Arbori de intervale Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.43 kb
#include <bits/stdc++.h>
using namespace std;

int n, m, v[100010], op, a, b, tree[400010];

void build(int node, int st, int dr)
{
    if(st == dr)
    {
        tree[node] = v[st];
        return ;
    }
    int mij = (st + dr) / 2;
    build(2 * node, st, mij);
    build(2 * node + 1, mij + 1, dr);
    tree[node] = max(tree[2 * node], tree[2 * node + 1]);
}

void update(int node, int st, int dr, int pos, int val)
{
    if(st == dr)
    {
        tree[node] = val;
        return;
    }
    int mij = (st + dr) / 2;
    if(pos <= mij)
        update(2 * node, st, mij, pos, val);
    else
        update(2 * node + 1, mij + 1, dr, pos, val);
    tree[node] = max(tree[2 * node], tree[2 * node + 1]);
}

int query(int node, int st, int dr, int s, int d)
{
    if(s <= st && dr <= d)
        return tree[node];
    int mij = (st + dr) / 2, ans1 = 0, ans2 = 0;
    if(s <= mij)
        ans1 = query(2 * node, st, mij, s, d);
    if(d > mij)
        ans2 = query(2 * node + 1, mij + 1, dr, s, d);
    return max(ans1, ans2);

}

int main()
{
    ifstream f("arbint.in");
    ofstream g("arbint.out");

    f >> n >> m;
    for(int i = 1; i <= n; i++)
        f >> v[i];
    build(1, 1, n);
    for(int i = 1; i <= m; i++)
    {
        f >> op >> a >> b;
        if(op == 0)
            g << query(1, 1, n, a, b) << "\n";
        else
            update(1, 1, n, a, b);
    }

    return 0;
}