Cod sursa(job #2865672)

Utilizator meinkampfEmanuel Pinzariu meinkampf Data 9 martie 2022 08:32:39
Problema Range minimum query Scor 0
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.74 kb
#include <bits/stdc++.h>
using namespace std;

ifstream fin("rmq.in");
ofstream fout("rmq.out");

/**
2^ (i - 1) + 2 ^ (i - 1) = 2 ^ i
rmq[i][j] = minimul pe intervalul (j, j + 2^i - 1)
*/

int rmq[20][100005], n, m, e[100005], x, y;

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

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

    for (i = 1; i <= e[n]; i++)
        for (j = 1; j <= n - (1 << i) + 1; j++)
        rmq[i][j] = min(rmq[i - 1][j], rmq[i - 1][j + (1 << i) - 1]);

    while (m--)
    {
        fin >> x >> y;
        i = e[y - x + 1];
        fout << min(rmq[i][x], rmq[i][y - (1 << i) + 1]) << "\n";
    }

    return 0;
}