Cod sursa(job #1970144)

Utilizator razvan99hHorhat Razvan razvan99h Data 18 aprilie 2017 22:22:27
Problema Arbori de intervale Scor 40
Compilator cpp Status done
Runda Arhiva educationala Marime 1.19 kb
#include <iostream>
#include <fstream>
#define DM 10005
using namespace std;
ifstream fin("arbint.in");
ofstream fout("arbint.out");
int arb[DM * 4], n, m, x, a, b;

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