Cod sursa(job #2753239)

Utilizator DianaZaharia132nr2Zaharia Diana Cristiana DianaZaharia132nr2 Data 21 mai 2021 21:02:23
Problema Arbori de intervale Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.21 kb
#include<fstream>
#include <bits/stdc++.h>
using namespace std;

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

int N, M;
int Arb[40000000];

int Query(int i, int L, int R, int l, int r)
{
    if(L >= l && R <= r)
        return Arb[i];

    int aux = L + (R - L) / 2;

    if(r <= aux)
        return Query(2 * i, L, aux, l, r);
    if(l >= aux + 1)
        return Query(2 * i + 1, aux + 1, R, l, r);

    return max(Query(2 * i, L, aux, l, aux), Query(2 * i + 1, aux + 1, R, aux + 1, r));
}

void Update(int i, int L, int R, int A, int B)
{
    if(L == R)
    {
        Arb[i] = B;
        return;
    }

    int aux = L + (R - L) / 2;

    if(A <= aux)
        Update(2 * i, L, aux, A, B);
    else
        Update(2 * i + 1, aux + 1, R, A, B);

    Arb[i] = max(Arb[2 * i], Arb[2 * i + 1]);
}

int main()
{
    int j, opt, a, b, x;
    f >> N>> M;
    for(j= 1; j<= N; j++)
    {
        f >> x;
        Update(1, 1, N, j, x);
    }

    for(j= 1; j<= M; j++)
    {
        f >>opt>> a >> b;

        if(opt== 0)
            g << Query(1, 1, N, a, b) <<"\n";
        else
            Update(1, 1, N, a, b);
    }

    f.close();
    g.close();
    return 0;
}