Cod sursa(job #1006247)

Utilizator R4DIC4LTeodorescu Oana Maria R4DIC4L Data 6 octombrie 2013 18:34:52
Problema Arbori de intervale Scor 50
Compilator cpp Status done
Runda Arhiva educationala Marime 1.33 kb
#include <fstream>
#define dim 100001
/// 2 * n - 1 noduri intr-un arbore de intervale
using namespace std;
ifstream f("arbint.in");
ofstream g("arbint.out");
int maxim, MaxArb[4 * dim + 1];
void Update(int nod, int st, int dr, int pos, int val)
{
    if(st == dr)
    {
        MaxArb[nod] = val;
        return;
    }
    int mij = (st + dr)/2;
    if(pos <= mij)
        Update(2 * nod, st, mij, pos, val);
    if(mij < pos)
        Update(2 * nod + 1, mij + 1, dr, pos, val);
    MaxArb[nod] = max(MaxArb[2 * nod], MaxArb[2 * nod + 1]);
}
void Query(int nod, int st, int dr, int p, int q)
{
    if(p <= st && dr <= q)
    {
        if(maxim < MaxArb[nod])
            maxim = MaxArb[nod];
        return;
    }
    int mij = (st + dr)/2;
    if(p <= mij)
        Query(2 * nod, st, mij, p, q);
    if(mij < q)
        Query(2 * nod + 1, mij + 1, dr, p, q);
}
int main ()
{
    int n, m, x, tip, a, b;
    f >> n >> m;
    for(int i = 1; i <= n; ++ i)
    {
        f >> x;
        Update(1, 1, n, i, x);
    }
    for(int i = 1; i <= m; ++ i)
    {
        f >> tip >> a >> b;
        if(tip == 0)
        {
            maxim = -1;
            Query(1, 1, n, a, b);
            g << maxim << '\n';
        }
        else
        {
            Update(1, 1, n, a, b);
        }
    }
    return 0;
}