Cod sursa(job #3265019)

Utilizator Bianca2507Negret Bianca Bianca2507 Data 26 decembrie 2024 15:38:53
Problema Arbori de intervale Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.39 kb
#include <fstream>
#include <set>
#include <climits>
#include <queue>
using namespace std;
ifstream cin("arbint.in");
ofstream cout("arbint.out");
int n,m,v[100005],aint[400005],maxi;
void build(int nod,int st,int dr)
{
    if(st==dr)
    {
        aint[nod]=v[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 poz,int val)
{
    if(st==dr)
    {
        aint[nod]=val;
        return;
    }
    int mid=(st+dr)/2;
    if(poz<=mid)
        update(2*nod,st,mid,poz,val);
    else
        update(2*nod+1,mid+1,dr,poz,val);
    aint[nod]=max(aint[2*nod],aint[2*nod+1]);
}
void query(int nod,int st,int dr,int a,int b)
{
    if(a<=st && dr<=b)
        maxi=max(maxi,aint[nod]);
    else
    {
        int mid=(st+dr)/2;
        if(a<=mid)
            query(2*nod,st,mid,a,b);
        if(b>=mid+1)
            query(2*nod+1,mid+1,dr,a,b);
    }
}
int main()
{
    cin>>n>>m;
    for(int i=1; i<=n; i++)
        cin>>v[i];
    build(1,1,n);
    for(int i=1; i<=m; i++)
    {
        int cer,a,b;
        cin>>cer>>a>>b;
        if(cer==1)
            update(1,1,n,a,b);
        else if(cer==0)
        {
            maxi=INT_MIN;
            query(1,1,n,a,b);
            cout<<maxi<<'\n';
        }
    }
    return 0;
}