Cod sursa(job #2183206)

Utilizator TimoteiCopaciu Timotei Timotei Data 22 martie 2018 22:06:18
Problema Range minimum query Scor 70
Compilator cpp Status done
Runda Arhiva educationala Marime 1.04 kb
#include <iostream>
#include <fstream>
#include <algorithm>
#include <cmath>

#define For(i, x, y) for(int i = x; i <= y; ++i)
#define Forr(i, x, y) for(int i = x; i >= y; --i)

using namespace std;

int n, m, M[100005][20], x, y, lg2[100005];

void set_lg2()
{
    int p = 2;
    lg2[1] = 0;
    while(p <= 100000){
        lg2[p] = lg2[p / 2] + 1;
        p *= 2;
    }
    For(i, 1, 100000)
      if(lg2[i] == 0) lg2[i] = lg2[i - 1];
}
void set_values()
{
    For(j, 1, lg2[n])
      For(i, 1, n - (1 << j) + 1){
         M[i][j] = min(M[i][j - 1], M[i + (1 << (j - 1))][j - 1]);
      }
}
int query(int x, int y){
  int mn = (1 << 30), p;
  while(x <= y){
    p = lg2[y - x + 1];
    mn = min(mn, M[x][p]);
    x += (1 << p);
  }
  return mn;
}
int main()
{
    ifstream fin("rmq.in");
    ofstream fout("rmq.out");
    fin >> n >> m;
    set_lg2();
    For(i, 1, n)
      fin >> M[i][0];
    set_values();
    For(i, 1, m){
      fin >> x >> y;
      fout << query(x, y) << '\n';
    }
    return 0;
}