Cod sursa(job #1922266)

Utilizator adystar00Bunea Andrei adystar00 Data 10 martie 2017 16:46:00
Problema Arbori de intervale Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.56 kb
#include <iostream>
#include <fstream>
using namespace std;
const int inf=1000100;
int arbint[400010],v[100010],ans;
void build (int node, int left, int right)
{
    if(left==right)
        arbint[node]=v[left];
    else
    {
        int mij = (left+right)/2;
        build(2*node,left,mij);
        build(2*node+1,mij+1,right);
        arbint[node]=max(arbint[2*node],arbint[2*node+1]);
    }
}
void update (int node, int left, int right, int a, int b)
{
    if(left==right)
        arbint[node]=b;
        else
        {
            int mij =(left + right)/2;
            if(mij<a)
                update(2*node+1,mij+1,right,a,b);
            else
                update(2*node,left,mij,a,b);
            arbint[node]=max(arbint[2*node],arbint[2*node+1]);
        }
}
int query (int node, int left, int right, int a, int b)
{
    if(left>=a&&b>=right)
        return arbint[node];
    else
    {
        int ans=-inf;
        int mij = (left + right)/2;
        if(b>mij)
            ans=max(ans,query(2*node+1,mij+1,right,a,b));
        if(a<=mij)
            ans=max(ans,query(2*node,left,mij,a,b));
        return ans;
    }
}
int main()
{
    ifstream fin ("arbint.in");
    ofstream fout ("arbint.out");
    int n,k,i,a,b,q,x;
    fin>>n>>k;
    for(i=1; i<=n; i++)
        fin>>v[i];
    build(1,1,n);
    for(i=1; i<=k; i++)
    {
        fin>>q>>a>>b;
        if(q==1)
        {
            update(1,1,n,a,b);
        }
        else
        {
            fout<<query(1,1,n,a,b)<<"\n";
        }
    }
    return 0;
}