Cod sursa(job #3328987)

Utilizator tudorr1istrate zeul meu tudorr1 Data 11 decembrie 2025 15:20:38
Problema Arbori de intervale Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.14 kb
#include<bits/stdc++.h>
using namespace std;
int a[100001],aint[400001];
void build(int l,int r,int id){
    if(l==r){
        aint[id]=a[l];
        return;
    }
    int mid=(l+r)/2;
    build(l,mid,2*id);
    build(mid+1,r,2*id+1);
    aint[id]=max(aint[2*id],aint[2*id+1]);
}
void update(int l,int r,int id,int pos,int val){
    if(l==r){
        a[l]=val;
        aint[id]=val;
        return;
    }
    int mid=(l+r)/2;
    if(pos<=mid) update(l,mid,2*id,pos,val);
    else update(mid+1,r,2*id+1,pos,val);
    aint[id]=max(aint[2*id],aint[2*id+1]);
}
int query(int l,int r,int ql,int qr,int id){
    if(qr<l||ql>r) return 0;
    if(ql<=l&&qr>=r) return aint[id];
    int mid=(l+r)/2;
    return max(query(l,mid,ql,qr,2*id),query(mid+1,r,ql,qr,2*id+1));
}
int32_t main(){
    ifstream cin("arbint.in");
    ofstream cout("arbint.out");
    int n,q;
    cin>>n>>q;
    for(int i=1;i<=n;i++) cin>>a[i];
    build(1,n,1);
    while(q--){
        int tip,l,r;
        cin>>tip>>l>>r;
        if(tip==1){
            update(1,n,1,l,r);
        }
        if(tip==0){
            cout<<query(1,n,l,r,1)<<'\n';
        }
    }
}