Cod sursa(job #2605296)

Utilizator VladNANegoita Vlad-Andrei VladNA Data 24 aprilie 2020 18:39:29
Problema Arbori de intervale Scor 0
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.36 kb
#include <iostream>
#include <cstdio>

using namespace std;

int p,val,n;
int arbmax[2*100000+10];

int maxim(int nr1, int nr2)
{
    if(nr1>nr2)
        return nr1;
    else
        return nr2;
}

void update(int st, int dr, int nod)
{
    if(st==dr)
    {
        arbmax[nod]=val;
    }
    else
    {
        int mij=(st+dr)/2;
        if(p<=mij && 2*nod<=2*n-1)
            update(st,mij,2*nod);
        if(p>mij && 2*nod+1<=2*n-1)
            update(mij+1,dr,2*nod+1);
        if(2*nod<=2*n-1)
            arbmax[nod]=maxim(arbmax[2*nod],arbmax[2*nod+1]);
    }
}

int query(int a, int  b, int nod, int st, int dr)
{
    if(a<=st && b>=dr)
        return arbmax[nod];
    else
    {
        int max1=0,max2=0,mij=(st+dr)/2;
        if(a<=mij && 2*nod<=2*n-1)
             max1=query(a,b,2*nod,st,mij);
        if(b>mij && 2*nod+1<=2*n-1)
             max2=query(a,b,2*nod+1,mij+1,dr);
        return maxim(max1,max2);
    }
}

int main()
{
    freopen("arbint.in","r",stdin);
    freopen("arbint.out","w",stdout);
    int i,m,x,a,b;
    cin>>n>>m;
    for(i=1;i<=n;i++)
    {
        cin>>val;
        p=i;
        update(1,n,1);
    }
    for(i=1;i<=m;i++)
    {
        cin>>x>>a>>b;
        if(x==0)
        {
            cout<<query(a,b,1,1,n)<<"\n\n\n";
        }
        else
        {
            p=a;
            val=b;
            update(1,n,1);
        }
    }
    return 0;
}