Cod sursa(job #3207066)

Utilizator AndreasBossGamerBaragau Andreas AndreasBossGamer Data 24 februarie 2024 21:41:56
Problema Range minimum query Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.08 kb
#include <fstream>
#include <vector>

using namespace std;

ifstream cin("rmq.in");
ofstream cout("rmq.out");

int n, q;
int rmq[18][100001];
int putere[18];

void precalcPuteri()
{
    putere[0] = 1;
    for (int i = 1; i <= 17; i++) putere[i] = putere[i - 1] * 2;
}

int bitSemnificativ[100001];
void ceva()
{
    bitSemnificativ[1] = 1;
    for (int i = 2; i <= 100000; i++)
        bitSemnificativ[i] = 1 + bitSemnificativ[i / 2];
}

int main()
{
    cin >> n >> q;
    for (int i = 1; i <= n; i++) cin >> rmq[0][i];
    precalcPuteri();
    ceva();
    for (int e = 1; putere[e] <= n; e++)
    {
        for (int i = 1; i <= n; i++)
        {
            rmq[e][i] = rmq[e - 1][i];
            int j = i + putere[e - 1];
            if (j <= n)
                rmq[e][i] = min(rmq[e][i], rmq[e - 1][j]);
        }
    }

    while (q--)
    {
        int st, dr;
        cin >> st >> dr;

        int e = bitSemnificativ[dr - st + 1];
        e--;
        int len = putere[e];     
        cout << min(rmq[e][st], rmq[e][dr - len + 1]) << '\n';
    }
}