Cod sursa(job #2883856)

Utilizator petru-robuRobu Petru petru-robu Data 1 aprilie 2022 22:04:05
Problema Range minimum query Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.76 kb
#include <bits/stdc++.h>
using namespace std;
ifstream fin("rmq.in");
ofstream fout("rmq.out");

int LOG[100001], n, m, x, y;
vector<int> rmq[100002];

void compute_log()
{
  LOG[1]=0;
  for(int i=2; i<=n; i++)
      LOG[i] = LOG[i/2] + 1;
}

void build_rmq()
{
  for(int p=1;p<=LOG[n];p++)
    for(int i=1; i<=n; i++)
    {
      if(i+(1<<p)-1 > n)
        break;
      rmq[i][p]=min(rmq[i][p-1], rmq[i+(1<<(p-1))][p-1]);
    }
}

int main()
{
  fin>>n>>m;
  compute_log();
  for(int i=1;i<=n;i++)
    {
      rmq[i].resize(LOG[n]+1);
      fin>>rmq[i][0];
    }
  build_rmq();

  for(int i=0; i<m; i++)
  {
    fin>>x>>y;
    int exp=LOG[y-x+1];
    fout<< min(rmq[x][exp], rmq[y - (1<<exp) +1][exp])<<'\n';
  }

  return 0;
}