Cod sursa(job #1740950)

Utilizator HuskyezTarnu Cristian Huskyez Data 12 august 2016 16:30:11
Problema Arbori de intervale Scor 40
Compilator cpp Status done
Runda Arhiva educationala Marime 1.21 kb
#include <iostream>
#include <cstdlib>
#include <cstdio>
#include <fstream>

#define in "arbint.in"
#define out "arbint.out"

using namespace std;

ifstream f(in);
ofstream g(out);

int arbore[2*100000+5];
int n, m;
int val;
int maxi;
int op, a, b;

void add(int nod, int st, int dr, int pos, int val)
{
    if(st == dr){
        arbore[nod] = val;
        return;
    }
    int mij = (st+dr)/2;
    if(pos <= mij){
        add(2*nod, st, mij, pos, val);
    }else{
        add(2*nod+1, mij+1, dr, pos, val);
    }
    arbore[nod] = max(arbore[2*nod], arbore[2*nod+1]);
}


void query(int nod, int st, int dr, int a, int b)
{
    if(a <= st and dr <= b){
        maxi = max(arbore[nod], maxi);
        return;
    }
    int mij = (st+dr)/2;
    if(a <= mij){
        query(2*nod, st, mij, a, b);
    }
    if(b > mij){
        query(2*nod+1, mij+1, dr, a, b);
    }
}

int main()
{
    f >> n >> m;

    for(int i=1; i<=n; i++){
        f >> val;
        add(1, 1, n, i, val);
    }

    for(int i=0; i<m; i++){
        f >> op >> a >> b;
        if(op == 0){
            maxi = -1;
            query(1, 1, n, a, b);
            g << maxi << '\n';
        }
        if(op == 1){
            add(1, 1, n, a, b);
        }
    }

    return 0;
}