Cod sursa(job #2176179)

Utilizator razvan99hHorhat Razvan razvan99h Data 16 martie 2018 21:24:47
Problema Arbori de intervale Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.22 kb
#include <iostream>
#include <fstream>
#include <vector>
#include <algorithm>
#define DM 100005
using namespace std;
ifstream fin("arbint.in");
ofstream fout("arbint.out");
int n, m, val, a, b, arb[DM * 4];

void update(int nod, int st, int dr, int poz, int val)
{
    if(st == dr)
    {
        arb[nod] = val;
        return;
    }
    int mij = (st + dr) / 2;
    if(poz <= mij)
        update(nod * 2, st, mij, poz, val);
    else
        update(nod * 2 + 1, mij + 1, dr, poz, val);
    arb[nod] = max(arb[nod * 2], arb[nod * 2 + 1]);
}
int query(int nod, int st, int dr, int a, int b)
{
    if(a <= st && dr <= b)
        return arb[nod];
    int mij = (st + dr) / 2, ret = -(1 << 31) + 1;
    if(a <= mij)
        ret = max(ret, query(nod * 2, st, mij, a, b));
    if(b >= mij + 1)
        ret = max(ret, query(nod * 2 + 1, mij + 1, dr, a, b));
    return ret;
}

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

    return 0;
}