Cod sursa(job #3333054)

Utilizator SGLDCASA SI PODUL SGLD Data 10 ianuarie 2026 18:07:21
Problema Arbori de intervale Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.46 kb
#include <fstream>

using namespace std;
ifstream in("arbint.in");
ofstream out("arbint.out");
int aint[400001];
int arr[100001];
void build(int node,int st,int dr)
{
    if(st==dr)
    {
        in>>aint[node];
        return;
    }
    else
    {
        int mid=(st+dr)/2;
        build(2*node,st,mid);
        build(2*node+1,mid+1,dr);
    }
    aint[node]=max(aint[node*2],aint[node*2+1]);
}
void update(int pos,int val,int node,int st,int dr)
{
    if(st==dr)
    {
        aint[node]=val;
        return;
    }
    else
    {
        int mid=(st+dr)/2;
        if(pos<=mid)
        {
            update(pos,val,2*node,st,mid);
        }
        else
        {
            update(pos,val,2*node+1,mid+1,dr);
        }
        aint[node]=max(aint[node*2],aint[node*2+1]);
    }
}
int query(int a,int b,int node,int st,int dr)
{
    if(st>b || dr<a)
    {
        return 0;
    }
    else if(a<=st && dr<=b)
    {
        return aint[node];
    }
    else
    {
        int mid=(st+dr)/2;
        int val1=query(a,b,2*node,st,mid);
        int val2=query(a,b,2*node+1,mid+1,dr);
        return max(val1,val2);
    }
}
int main()
{
    int n,m;
    in>>n>>m;
    build(1,1,n);
    int a,b,c;
    for(int i=1; i<=m; i++)
    {
        in>>a>>b>>c;
        if(a==0)
        {
            out<<query(b,c,1,1,n)<<endl;
        }
        else
        {
            update(b,c,1,1,n);
        }
    }
    return 0;
}