Cod sursa(job #3030805)

Utilizator Luka77Anastase Luca George Luka77 Data 17 martie 2023 21:32:28
Problema Arbori de intervale Scor 40
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.47 kb
#include <bits/stdc++.h>
#define NMAX 100005
using namespace std;

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

struct Arbint
{
    vector<int>arb;
    int len = 0;

    Arbint(int n)
    {
        arb.resize(n + 5, 0);
        len = n + 5;
    }

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

    inline int query(int node, int st, int dr, int arbst, int arbdr)
    {
        if(st > arbdr || dr < arbst)
            return 0;
        if(st >= arbst && dr <= arbdr)
        {
            return arb[node];
        }
        int mid = (st + dr) / 2;
        return max(query(node * 2, st, mid, arbst, arbdr), query(node * 2 + 1, mid + 1, dr, arbst, arbdr));
    }
};

int n, q;
Arbint arb(NMAX);

int main()
{
    fin >> n >> q;

    for(int i = 1; i <= n; ++ i)
    {
        int x;
        fin >> x;
        arb.update(1, 1, n, i, x);
    }

    while(q--)
    {
        bool tip;
        int a, b;
        fin >> tip >> a >> b;
        if(!tip)
        {
            fout << arb.query(1, 1, n, a, b) << '\n';
        }
        else
        {
            arb.update(1, 1, n, a, b);
        }
    }
}