Cod sursa(job #2238790)

Utilizator al3xionescuIonescu Alexandru al3xionescu Data 7 septembrie 2018 17:02:38
Problema Arbori de intervale Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.19 kb
#include <bits/stdc++.h>
using namespace std;
ifstream in("arbint.in");
ofstream out("arbint.out");
const int NMAX = 1e5 + 5;
int tree[4*NMAX], pos, val, l, r, rez;
void update(int root, int st, int dr)
{
    if (st == dr)
        tree[root] = val;
    else
    {
        int m = (st+dr)/2;
        if (pos<=m)
            update(2*root,st,m);
        else
            update(2*root+1,m+1,dr);
        tree[root] = max(tree[2*root],tree[2*root+1]);
    }
}
 
void query(int root, int st, int dr)
{
    if (l<=st && dr<=r)
        rez = max(rez,tree[root]);
    else
    {
        int m = (st+dr)/2;
        if (l<=m)
            query(2*root,st,m);
        if (r>m)
            query(2*root+1,m+1,dr);
    }
}
int main(){
    int n, m;
    in >> n >> m;
    for(int i = 1; i <= n; i++){
        int x;
        in >> x;
        pos = i;
        val = x;
        update(1, 1, n);
    }
    for(int i = 1; i <= m; i++){
        int t,x,y;
        in >> t >> x >> y;
        if(!t){
            rez = -1;
            l = x;
            r = y;
            query(1,1,n);
            out << rez << "\n";
        }
        else{
            pos = x;
            val = y;
            update(1, 1, n);
        }
    }
    return 0;
}