Cod sursa(job #3269020)

Utilizator robert_dumitruDumitru Robert Ionut robert_dumitru Data 18 ianuarie 2025 10:22:06
Problema Range minimum query Scor 0
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.93 kb
#include <bits/stdc++.h>
using namespace std;

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

int n, m, q;
int rmq[18][100005], e[100005], a[100005];

void BuildRMQ()
{
    int i, j, L;
    m = log2(n);
    for (i = 2; i <= m; i *= 2)
        e[i] = 1;
    for (i = 1; i <= n; i++)
        e[i] += e[i - 1];
    for (i = 1; i <= n; i++)
        rmq[0][i] = a[i];
    for (i = 1; i <= m; i++)
    {
        L = (1 << (i - 1));
        for (j = 1; j <= n - L + 1; j++)
            rmq[i][j] = min(rmq[i - 1][j], rmq[i - 1][j + L]);
    }
}
int Query(int st, int dr)
{
    int L, expo;
    L = dr - st + 1;
    expo = e[L];
    return min(rmq[expo][st], rmq[expo][dr - (1 << expo) + 1]);
}

int main()
{
    int i, j;
    fin >> n >> q;
    for (i = 1; i <= n; i++)
        fin >> a[i];
    BuildRMQ();
    while (q--)
    {
        fin >> i >> j;
        fout << Query(i, j) << "\n";
    }
    return 0;
}