Cod sursa(job #1619001)

Utilizator bullracerGabriel bullracer Data 28 februarie 2016 10:54:45
Problema Arbori de intervale Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.21 kb
#include <fstream>

#define NMAX 100007

using namespace std;

ifstream cin("arbint.in");
ofstream cout("arbint.out");

int Arbi[4 * NMAX];
int n, m, Ans;

void update(int Node, int st, int dr, int poz, int val){
    if(st == dr){
        Arbi[Node] = val;
        return ;
    }
    int med = (st + dr) >> 1;
    if(poz > med)
        update(Node * 2 + 1, med + 1, dr, poz, val);
    else
        update(Node * 2, st, med, poz, val);
    Arbi[Node] = max(Arbi[Node * 2], Arbi[Node * 2 + 1]);
}

void query(int Node, int st, int dr, int x, int y){
    if(st >= x && dr <= y){
        Ans = max(Ans, Arbi[Node]);
        return ;
    }
    int med = (st + dr) >> 1;
    if(med >= x)
        query(Node * 2, st, med, x, y);
    if(med < y)
        query(Node * 2 + 1, med + 1, dr, x, y);
}

int main(){
    cin >> n >> m;
    for(int i = 1; i <= n; ++i){
        int a;
        cin >> a;
        update(1, 1, n, i, a);
    }
    while(m--){
        int Type, a, b;
        cin >> Type >> a >> b;
        if(Type == 0){
            Ans = 0;
            query(1, 1, n, a, b);
            cout << Ans << "\n";
        }
        else
            update(1, 1, n, a, b);
    }
    return 0;
}