Cod sursa(job #3206417)

Utilizator Bogdan345Marius Mihalache Bogdan345 Data 22 februarie 2024 17:56:03
Problema Arbori de intervale Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.5 kb
#include <fstream>
#include <vector>
using namespace std;
ifstream cin("arbint.in");
ofstream cout("arbint.out");
vector<int>arbore,v;
void initializare(int nod,int st,int dr){
    if(st==dr){
        arbore[nod]=v[st];
        return;
    }
    int mij=(st+dr)/2;
    initializare(2*nod,st,mij);
    initializare(2*nod+1,mij+1,dr);
    arbore[nod]=max(arbore[2*nod],arbore[2*nod+1]);
}
void actualizare(int nod,int st,int dr,int poz,int val){
    if(st==dr){
        arbore[nod]=val;
        v[poz]=val;
        return;
    }
    int mij=(st+dr)/2;
    if(poz<=mij){
        actualizare(2*nod,st,mij,poz,val);
    }else{
        actualizare(2*nod+1,mij+1,dr,poz,val);
    }
    arbore[nod]=max(arbore[2*nod],arbore[2*nod+1]);
}
int interogare(int nod,int st,int dr,int a,int b){
    if( a<=st && dr<=b){
        return arbore[nod];
    }
    int mij=(st+dr)/2;
    int val=0;
    if(a<=mij){
        val=max(val,interogare(2*nod,st,mij,a,b));
    }
    if(mij+1<=b){
        val=max(val,interogare(2*nod+1,mij+1,dr,a,b));
    }
    return val;
}
int main(){
    ios::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
    int n,m;
    cin>>n>>m;
    arbore.resize(4*n);
    v.resize(n+1);
    for(int i=1;i<=n;i++){
        cin>>v[i];
    }
    initializare(1,1,n);
    int c,a,b;
    for(int i=1;i<=m;i++){
        cin>>c>>a>>b;
        if(c==0){
            cout<<interogare(1,1,n,a,b)<<'\n';
        }else{
            actualizare(1,1,n,a,b);
        }
    }
}