Cod sursa(job #3213813)

Utilizator SerbanCaroleSerban Carole SerbanCarole Data 13 martie 2024 14:36:17
Problema Arbori de intervale Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.66 kb
#include <fstream>
#include <vector>
#include <algorithm>
using namespace std;
using pii = pair<int,int>;
ifstream cin("arbint.in");
ofstream cout("arbint.out");
int n , m , op , a , b;
struct segt
{
    int aint[400001];
    void update(int nod , int st , int dr , int &poz , int &val)
    {
        if(st == dr) aint[nod] = val;
        else
        {
            int mij = st + (dr-st)/2;
            if(poz <= mij) update(nod*2,st,mij,poz,val);
            else update(nod*2+1,mij+1,dr,poz,val);
            aint[nod] = max(aint[nod*2],aint[nod*2+1]);
        }
    }
    int query(int nod , int st , int dr , int &qst , int &qdr)
    {
        if(qst <= st && dr <= qdr)
        {
            return aint[nod];
        }
        else
        {
            int mij = st + (dr-st)/2;
            int val = -1;
            if(qst <= mij) val = max(val,query(nod*2,st,mij,qst,qdr));
            if(qdr > mij) val = max(val,query(nod*2+1,mij+1,dr,qst,qdr));
            return val;
        }
    }
    void build(int nod ,int st , int dr)
    {
        if(st == dr)
        {
            cin >> aint[nod];
        }
        else
        {
            int mij = st + (dr-st)/2;
            build(nod*2,st,mij);
            build(nod*2+1,mij+1,dr);
            aint[nod] = max(aint[nod*2],aint[nod*2+1]);
        }
    }
}arb;
signed main()
{
    cin >> n >> m;
    arb.build(1,1,n);
    for(int i = 1 ; i <= m ; ++i)
    {
        cin >> op >> a >> b;
        if(op == 0)
        {
            cout << arb.query(1,1,n,a,b) << '\n';
        }
        else
        {
            arb.update(1,1,n,a,b);
        }
    }
    return 0;
}