Cod sursa(job #2729129)

Utilizator avtobusAvtobus avtobus Data 24 martie 2021 12:00:05
Problema Arbori de intervale Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.28 kb
#include <stdio.h>
#include <bits/stdc++.h>

#define rep(i, n) for(int i = 0; i < (int)(n); i++)

using namespace std;
typedef long long ll;
typedef pair<int, int> pii;
typedef vector<int> vi;
// const int INF = 0x3f3f3f3f;

ifstream fin {"arbint.in"};
ofstream fout {"arbint.out"};

const int Nmax = 1<<18;
int N, M;
int arb[Nmax];

void arb_insert(int nod, int l, int r, int pos, int val) {
  if (l == r) {
    arb[nod] = val;
    return;
  }
  int m = (l + r) / 2;
  if (pos <= m) { arb_insert(2*nod, l, m, pos, val); }
  else { arb_insert(2*nod+1, m+1, r, pos, val); }

  arb[nod] = max(arb[2*nod], arb[2*nod+1]);
}

int arb_query(int nod, int l, int r, int a, int b) {
  if (a <= l && r <= b) {
    return arb[nod];
  }
  int m = (l+r)/2;
  int res = 0;
  if (m >= a) { res = max(res, arb_query(2*nod, l, m, a, b)); }
  if (m < b) { res = max(res, arb_query(2*nod+1, m+1, r, a, b)); }
  return res;
}

int main(void) {
  // freopen("arbint.in", "r", stdin);
  std::ios_base::sync_with_stdio(false);
  std::cin.tie(NULL);
  int q, a, b;
  fin >> N >> M;
  rep(i, N) {
    fin >> a;
    arb_insert(1, 1, N, i+1, a);
  }
  rep(i, M) {
    fin >> q >> a >> b;
    if (q == 0) {
      fout << arb_query(1, 1, N, a, b) << '\n';
    } else if (q == 1) {
      arb_insert(1, 1, N, a, b);
    }
  }

  return 0;
}