Cod sursa(job #2032715)

Utilizator MoodyFaresFares Mohamad MoodyFares Data 5 octombrie 2017 16:51:39
Problema Arbori de intervale Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.28 kb
#include <cstdio>
#include <algorithm>
using namespace std;
const int NMAX = 100000;
int v[NMAX * 4 + 5];
void update(int nod, int poz, int val, int st, int dr)
{
  if(st == dr) {
        v[nod] = val;
        return ;
      }
    int mij = (st + dr) / 2;
    if(poz <= mij) {
        update(nod * 2, poz, val, st, mij);
      }
    else {
        update(nod * 2 + 1, poz, val, mij + 1, dr);
      }
    v[nod] = max(v[nod * 2], v[nod * 2 + 1]);
}
int query(int nod, int a, int b, int st, int dr)
{
    if(a <= st && dr <= b) {
        return v[nod];
      }
    int sol1 = 0, sol2 = 0;
    int mij = (st + dr) / 2;
    if(a <= mij) {
        sol1 = query(nod * 2, a, b, st, mij);
      }
    if(mij < b) {
        sol2 = query(nod * 2 + 1, a, b, mij + 1, dr);
      }
    return max(sol1, sol2);
}
 
int main()
{
    int n, m;
    freopen("arbint.in", "r", stdin);
    freopen("arbint.out", "w", stdout);
    scanf("%d%d", &n, &m);
    for(int i = 1; i <= n; ++i) {
        int val;
        scanf("%d", &val);
        update(1, i, val, 1, n);
      }
    for(int q = 0; q < m; ++q) {
        int t, a, b;
        scanf("%d%d%d", &t, &a, &b);
        if(t == 1) {
            update(1, a, b, 1, n);
          }
        else {
            printf("%d\n", query(1, a, b, 1, n));
          }
      }
    return 0;
}