Cod sursa(job #2168296)

Utilizator waren4Marius Radu waren4 Data 14 martie 2018 10:19:58
Problema Arbori de intervale Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.16 kb
#include <iostream>
#include <fstream>
#include <algorithm>

using namespace std;

ifstream f("arbint.in"); ofstream g("arbint.out");
int n,m,ans,x,y,c,arb[400003];

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

void query(int nod, int st, int dr, int x, int y) {
    int mij = (st + dr) / 2;
    if(st >= x && dr <= y) {
        ans = max(ans,arb[nod]);
        return;
    }
    if(y > mij) {
        query(nod*2+1,mij+1,dr,x,y);
    }
    if(x <= mij) {
        query(nod*2,st,mij,x,y);
    }
}

int main() {
    int i,j;
    f>>n>>m;
    for(i = 1; i <= n; ++i) {
        f>>x;
        update(1,1,n,i,x);
    }
    for(i = 1; i <= m; ++i) {
        f>>c>>x>>y;
        if (c) {
            update(1,1,n,x,y);
        }
        else {
            ans = 0;
            query(1,1,n,x,y);
            g<<ans<<'\n';
        }
    }
    return 0;
}