Cod sursa(job #2019758)

Utilizator gavra_bogdanBogdan Gavra gavra_bogdan Data 8 septembrie 2017 14:32:24
Problema Arbori de intervale Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.04 kb
#include <bits/stdc++.h>

using namespace std;
int val[400000];
int query(int nod,int a,int b,int x,int y)
{
    if(b<x or a>y)
        return 0;
    if(b<=y&&a>=x)
        return val[nod];
    return max(query(2*nod,a,(a+b)/2,x,y),
               query(2*nod+1,(a+b)/2+1,b,x,y));
}
void update(int nod,int a,int b,int pos,int v)
{
    if(pos<a or pos>b)
        return;
    if(a==b)
    {
        val[nod]=v;
        return;
    }
    update(2*nod,a,(a+b)/2,pos,v);
    update(2*nod+1,(a+b)/2+1,b,pos,v);
    val[nod]=max(val[2*nod],val[2*nod+1]);
}
int main()
{
    freopen("arbint.in","r",stdin);
    freopen("arbint.out","w",stdout);
    int n,m,v,x,y;
    scanf("%d%d",&n,&m);
    for(int i=1;i<=n;i++)
        {
            cin>>v;
            update(1,1,n,i,v);
        }
    for(int i=1;i<=m;i++)
    {
        scanf("%d%d%d",&v,&x,&y);
        if(v==0)
        {
            printf("%d\n",query(1,1,n,x,y));
        }
        else
        {
            update(1,1,n,x,y);
        }
    }
    return 0;
}