Cod sursa(job #1795370)

Utilizator danstefanDamian Dan Stefan danstefan Data 2 noiembrie 2016 11:47:05
Problema Arbori de intervale Scor 0
Compilator cpp Status done
Runda Arhiva educationala Marime 0.86 kb
#include <bits/stdc++.h>
using namespace std;
int n,m,i,op,x,y,v[100010];
void build()
{
    for(i=n-1; i>=0; --i)
        v[i]=max(v[i*2],v[i*2+1]);
}
void update(int poz,int val)
{
    int i;
    poz+=n-1;
    v[poz]=val;
    for(i=poz/2; i; i/=2)
        v[i]=max(v[i*2],v[i*2+1]);
}
int query(int l,int r)
{
    int ans=-1;
    l+=n-1;
    r+=n;
    while(l<r)
    {
        if(l&1)ans=max(ans,v[l++]);
        if(r&1)ans=max(ans,v[r--]);
        l/=2;
        r/=2;
    }
    return ans;
}

int main()
{
    freopen("arbint.in","r",stdin);
    freopen("arbint.out","w",stdout);
    scanf("%d%d",&n,&m);
    for(i=0; i<n; ++i)
        scanf("%d",&v[i+n]);
    build();
    for(i=1; i<=m; ++i)
    {
        scanf("%d%d%d",&op,&x,&y);
        if(op==0)printf("%d\n",query(x,y));
        else update(x,y);
    }
    return 0;
}