Cod sursa(job #2369981)

Utilizator Luca19Hritcu Luca Luca19 Data 6 martie 2019 10:06:26
Problema Range minimum query Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.76 kb
#include <fstream>

using namespace std;

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

int i, j, n, m, x, y;
int rmq[18][100005], log2[100005];

int query(int x, int y)
{
    int diff = y-x+1;
    int i = log2[diff];
    int a = rmq[i][x], b = rmq[i][y - (1 << i) + 1];
    return min(a, b);
}

int main()
{
    f >> n >> m;
    for (i = 1; i <= n; i++)
        f >> rmq[0][i];

    for (i = 2; i <= n; i++)
        log2[i] = log2[i/2] + 1;

    for (i = 1; (1 << i) <= n; i++)
        for (j = 1; j + (1 << i) - 1 <= n; j++)
        {
            x = rmq[i-1][j];
            y = rmq[i-1][j + (1 << (i-1))];
            rmq[i][j] = min(x, y);
        }

    while (m--)
    {
        f >> x >> y;
        g << query(x, y) << '\n';
    }
}