Cod sursa(job #1221189)

Utilizator Paula-ElenaPaula-Elena Margarit Paula-Elena Data 19 august 2014 20:32:40
Problema Range minimum query Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.84 kb
#include <fstream>
using namespace std;

const int MAXN = 1e5 + 3, LOG = 17;

int N, M, rmq[LOG][MAXN];

inline int minim(int a, int b)
{
    return a < b ? a : b;
}

inline int query(int st, int dr)
{
    int log = 31 - __builtin_clz(dr - st + 1);
    return minim( rmq[log][st], rmq[log][dr - (1 << log) + 1] );
}

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

    fin >> N >> M;
    for (int i = 1; i <= N; ++i)
        fin >> rmq[0][i];

    int log = 31 - __builtin_clz(N);
    for (int i = 1; i <= log; ++i)
        for (int j = 1; j <= N; ++j)
            rmq[i][j] = minim( rmq[i-1][j], rmq[i-1][j + (1 << (i-1) )] );

    while ( M-- )
    {
        int x, y;
        fin >> x >> y;
        fout << query(x, y) << '\n';
    }

    fin.close();
    fout.close();

    return 0;
}