Cod sursa(job #3343621)

Utilizator Dia3141Costea Diana Stefania Dia3141 Data 27 februarie 2026 20:46:01
Problema Arbori de intervale Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.21 kb
#include <fstream>
#define nmax (int)(1e5+1)
using namespace std;
ifstream cin("arbint.in");
ofstream cout("arbint.out");
int n,q,aint[4*nmax],a[nmax],tip,x,y;
void build(int nod,int st,int dr){
    if(st==dr){
        aint[nod]=a[st];
        return;
    }
    int mid=(st+dr)/2;
    build(2*nod,st,mid);
    build(2*nod+1,mid+1,dr);
    aint[nod]=max(aint[2*nod],aint[2*nod+1]);
}
void update(int nod,int st,int dr,int x,int y){
    if(st==dr){
        aint[nod]=a[st]=y;
        return ;
    }
    int mid=(st+dr)/2;
    if(x<=mid)
        update(2*nod,st,mid,x,y);
    else
        update(2*nod+1,mid+1,dr,x,y);
    aint[nod]=max(aint[2*nod],aint[2*nod+1]);
}
int query(int nod,int st,int dr,int x,int y){
    if(x<=st&&dr<=y)
        return aint[nod];
    int mid=(st+dr)/2,maxi=0;
    if(x<=mid)
        maxi=query(2*nod,st,mid,x,y);
    if(mid<y)
        maxi=max(maxi,query(2*nod+1,mid+1,dr,x,y));
    return maxi;
}
int main()
{
    cin>>n>>q;
    for(int i=1;i<=n;i++)
        cin>>a[i];
    build(1,1,n);
    while(q--){
        cin>>tip>>x>>y;
        if(tip==0)
            cout<<query(1,1,n,x,y)<<'\n';
        else
            update(1,1,n,x,y);
    }
    return 0;
}