Cod sursa(job #1142802)

Utilizator manutrutaEmanuel Truta manutruta Data 14 martie 2014 11:26:42
Problema Arbori de intervale Scor 50
Compilator cpp Status done
Runda Arhiva educationala Marime 1.3 kb
#include <iostream>
#include <fstream>

using namespace std;

#define MAXN 100005

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

int n;
int a[MAXN], aint[2 * MAXN];

void update(int poz, int val, int st = 1, int dr = n, int nod = 1)
{
    if (st == dr) {
        aint[nod] = val;
        return ;
    }

    int mij = ((st + dr) >> 1);

    if (poz <= mij) {
       update(poz, val, st, mij, nod << 1);
    } else {
        update(poz, val, mij + 1, dr, (nod << 1) + 1);
    }
    aint[nod] = max(aint[nod << 1], aint[(nod << 1) + 1]);
}

int query(int x, int y, int st = 1, int dr = n, int nod = 1)
{
    if (x <= st && dr <= y) {
        return aint[nod];
    }

    int mx = 0;
    int mij = ((st + dr) >> 1);
    if (x <= mij) {
        mx = max(mx, query(x, y, st, mij, nod << 1));
    }
    if (y > mij) {
        mx = max(mx, query(x, y, mij + 1, dr, (nod << 1) + 1));
    }
    return mx;
}

int main()
{
    int m;
    f >> n >> m;
    for (int i = 1; i <= n; i++) {
        int x;
        f >> x;
        update(i, x);
    }

    for (int i = 1; i <= m; i++) {
        int op, x, y;
        f >> op >> x >> y;

        switch (op) {
            case 0: g << query(x, y) << '\n'; break;
            case 1: update(x, y); break;
        }
    }
}