Cod sursa(job #1529776)

Utilizator vladnosVlad Persa vladnos Data 21 noiembrie 2015 11:15:54
Problema Range minimum query Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.15 kb
#include <iostream>
#include <fstream>

using namespace std;

ifstream f("rmq.in");
ofstream g("rmq.out");

//ifstream f("date.in");
//ofstream g("date.out");

/// log2 N : for (int i = 1; (1 << i) <= N; i++)

int     rmq[18][100005], v[100005], log[100005];
int     n, m;

/// log[X] = log2 X

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

int     ft_min(int a, int b)
{
    return a <= b ? a : b;
}

int     query(int x, int y)
{
    int     i;

    i = log[y - x + 1];
    return  (ft_min(rmq[i][x], rmq[i][y - (1 << i) + 1]));
}

void    rezolvare(void)
{
    int     x;
    int     y;

    f >> n >> m;
    for (int i = 1; i <= n; i++)
    {
        f >> v[i];
        rmq[0][i] = v[i];
    }
    for (int i = 1; (1 << i) <= n; i++)
    {
        for (int j = 1; j + (1 << (i - 1)) <= n; j++)
            rmq[i][j] = ft_min(rmq[i - 1][j], rmq[i - 1][j + (1 << (i - 1))]);
    }
    make_log();
    for (int i = 1; i <= m; i++)
    {
        f >> x >> y;
        g << query(x, y) << '\n';
    }
}
int main()
{
    rezolvare();
    return 0;
}