Cod sursa(job #3126057)

Utilizator rapidu36Victor Manz rapidu36 Data 5 mai 2023 15:14:11
Problema Range minimum query Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.04 kb
#include <fstream>

using namespace std;

const int N = 1e5;
const int L = 16;

int n, rmq[L+1][N+1], log2[N+1];

void constructie_rmq()
{
    for (int i = 1; (1 << i) <= n; i++)
    {
        for (int j = 1 << i; j <= n; j++)
        {
            rmq[i][j] = min(rmq[i-1][j-(1<<(i-1))], rmq[i-1][j]);
        }
    }
}

void constructie_log2()
{
    log2[1] = 0;
    for (int i = 2; i <= n; i++)
    {
        log2[i] = 1 + log2[i/2];
    }
}

int interogare(int st, int dr)
{
    int e = log2[dr-st+1];
    int p = 1 << e;
    return min(rmq[e][st+p-1], rmq[e][dr]);
}

int main()
{
    ifstream in("rmq.in");
    ofstream out("rmq.out");
    int nq;
    in >> n >> nq;
    for (int j = 1; j <= n; j++)
    {
        in >> rmq[0][j];
    }
    constructie_rmq();
    constructie_log2();
    for (int i = 0; i < nq; i++)
    {
        int st, dr;
        in >> st >> dr;
        if ( st > dr)
        {
            swap(st, dr);
        }
        out << interogare(st, dr) << "\n";
    }
    return 0;
}