Cod sursa(job #1510359)

Utilizator sebinechitasebi nechita sebinechita Data 24 octombrie 2015 21:17:30
Problema Arbori de intervale Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.25 kb
#include <iostream>
#include <fstream>
using namespace std;
ifstream fin("arbint.in");
ofstream fout("arbint.out");
#define MAX 100010

int aint[4 * MAX];
int l, r, ind;
void update(int nod, int st, int dr, int val)
{
    if(st == dr)
    {
        aint[nod] = val;
        return;
    }
    int mij = (st + dr) >> 1;
    if(ind <= mij)
        update(2 * nod, st, mij, val);
    else
        update(2 * nod + 1, mij + 1, dr, val);
    aint[nod] = max(aint[2 * nod], aint[2 * nod + 1]);
}

int query(int nod, int st, int dr)
{
    if(l <= st && dr <= r)
        return aint[nod];
    int mij = (st + dr) >> 1;
    int rez = 0;
    if(l <= mij)
        rez = max(rez, query(2 * nod, st, mij));
    if(mij + 1 <= r)
        rez = max(rez, query(2 * nod + 1, mij + 1, dr));
    return rez;
}

int main()
{
    int n, i, x, m, t, y;
    fin >> n >> m;
    for(i = 1 ; i <= n ; i++)
    {
        fin >> x;
        ind = i;
        update(1, 1, n, x);
    }
    while(m--)
    {
        fin >> t >> x >> y;
        if(t == 0)
        {
            l = x;
            r = y;
            fout << query(1, 1, n) << "\n";
        }
        else
        {
            ind = x;
            update(1, 1, n, y);
        }
    }
}