Cod sursa(job #2175027)

Utilizator razvan99hHorhat Razvan razvan99h Data 16 martie 2018 14:48:52
Problema Range minimum query Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.85 kb
#include <iostream>
#include <fstream>
#define DM 100005
using namespace std;
ifstream fin("rmq.in");
ofstream fout("rmq.out");
int n, m, x, y, rmq[20][DM], v[DM], log[DM];

void build_rmq()
{
    log[0] = -1;
    for(int i = 1; i <= n; i++)
        log[i] = 1 + log[i / 2];

    for(int i = 1; i <= n; i++)
        rmq[0][i] = v[i];

    for(int k = 1; k <= log[n]; k++)
        for(int i = 1; i + (1 << k) - 1 <= n; i++)
            rmq[k][i] = min(rmq[k - 1][i], rmq[k - 1][i + (1 << (k - 1))]);
}
int query(int x, int y)
{
    int l = log[y - x + 1];
    return min(rmq[l][x], rmq[l][y - (1 << l) + 1]);
}
int main()
{
    fin >> n >> m;
    for(int i = 1; i <= n; i++)
        fin >> v[i];

    build_rmq();

    for(int i = 1; i <= m; i++)
    {
        fin >> x >> y;
        fout << query(x, y) << '\n';
    }
    return 0;
}