Cod sursa(job #3272584)

Utilizator WiseAndrei4Vetrila Andrei WiseAndrei4 Data 30 ianuarie 2025 00:26:58
Problema Arbori de intervale Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.33 kb
#include <iostream>
#include <fstream>
using namespace std;
ifstream fin("arbint.in");
ofstream gout("arbint.out");
int *tree=new int[400005],*v=new int[100001];
void build(int nod,int l, int r)
{
    if(l==r)tree[nod]=v[l];
    else
    {
        build(2*nod,l,(l+r)/2);
        build(2*nod+1,(l+r)/2+1,r);
        tree[nod]=max(tree[2*nod],tree[2*nod+1]);
    }
}
void update(int nod,int l,int r,int a,int b)
{
    if(l==r&&l==a)tree[nod]=b;
    else
    {
        int m=(l+r)/2;
        if(a<=m)update(2*nod,l,m,a,b);
        else update(2*nod+1,m+1,r,a,b);
        tree[nod]=max(tree[2*nod],tree[2*nod+1]);
    }
}
int query(int nod,int l,int r,int x,int y)
{
    //cout<<l<<' '<<r<<' '<<x<<' '<<y<<' '<<tree[nod]<<endl;
    if(x>y)return 0;
    if(l==x&&r==y)return tree[nod];
    int m=(l+r)/2;
    //return max(query(2*nod,l,m,x,y),query(2*nod+1,m+1,r,x,y));
    return max(query(2*nod,l,m,x,min(y,m)),
               query(2*nod+1,m+1,r,max(x,m+1),y));
}
int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
    int n,q,tip,a,b;
    fin>>n>>q;
    for(int i=1; i<=n; ++i)fin>>v[i];
    build(1,1,n);
    while(q--)
    {
        fin>>tip>>a>>b;
        if(tip==0)
            gout<<query(1,1,n,a,b)<<'\n';
        else
            update(1,1,n,a,b);
    }
    return 0;
}