Cod sursa(job #2759300)

Utilizator AlexNic_Nicula Dan Alexandru AlexNic_ Data 16 iunie 2021 18:11:37
Problema Arbori de intervale Scor 40
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.11 kb
#include <fstream>
#define M 100001
#define INF 10000000
using namespace std;

ifstream cin("arbint.in");
ofstream cout("arbint.out");

int t[M],x;

void actualizare(int p, int st, int dr, int poz, int val){
    if(st==dr){
        t[p]=val; return;
    }
    int m=(st+dr)/2 , fs=2*p , fd=2*p+1;
    if(poz<=m){actualizare(fs,st,m,poz,val);}
    else{actualizare(fd,m+1,dr,poz,val);}
    t[p]=max(t[fs],t[fd]);
}

int interogare(int p, int st, int dr, int a, int b){

    /// max([st;dr] intersectat cu [a;b])

    if(a<=st && dr<=b){
        return t[p];
    }
    int m=(st+dr)/2 , fs=2*p, fd=2*p+1;
    int rs= -INF , rd= -INF;
    if(a<=m){rs=interogare(fs,st,m,a,b);}
    if(m<b){rd=interogare(fd,m+1,dr,a,b);}
    return max(rs,rd);
}

int main()
{
    int n, q, t, a , b;
    cin>>n>>q;
    for(int i=1;i<=n;i++){
        cin>>x;
        actualizare(1,1,n,i,x);
    }
    for(int i=1;i<=q;i++){
        cin>>t>>a>>b;
        if(t==0){
            cout<<interogare(1,1,n,a,b)<<'\n';
        }
        else{
            actualizare(1,1,n,a,b);
        }
    }
    return 0;
}