Cod sursa(job #1673180)

Utilizator catu_bogdan_99Catu Bogdan catu_bogdan_99 Data 3 aprilie 2016 15:23:09
Problema Range minimum query Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.21 kb
#include <cstdio>
#define DIM 100005
#define DIMlg 18
using namespace std;

int rmq[DIMlg][DIM];
int log[DIM];

int minim( int a, int b );
void precalculare_log( int n );
void precalculare_rmq( int n );

int main()
{

    freopen("rmq.in","r",stdin);
    freopen("rmq.out","w",stdout);

    int n, m, i, j, s, t, d, k, p, q;

    scanf("%d%d",&n,&m);
    for( i = 1; i <= n; ++i )
        scanf("%d",&rmq[0][i]);


    precalculare_log( n );
    precalculare_rmq( n );

    for( i = 1; i <= m; ++i ){
        scanf("%d%d",&p,&q);
        d = log[q-p+1];
        printf("%d\n",minim( rmq[d][p], rmq[d][q-(1<<d)+1]));
    }


    return 0;
}

int minim( int a, int b ){
    if( a > b ) return b;
    return a;
}

/**Precalculare valori logaritmi de intervale*/
void precalculare_log( int n ){
    int i;

    log[1] = 0;
    for( i = 2; i <= n; ++i ){
        log[i] = log[i/2] + 1;
    }

}

/**Precalculam rmq pentru puterile lui 2*/
void precalculare_rmq( int n ){

    int i, j, p;

    for( i = 1; (1<<i) <= n; ++i ){
        for( j = 1; j + (1<<i) - 1 <= n; ++j ){
            p = 1<<(i-1);
            rmq[i][j] = minim( rmq[i-1][j], rmq[i-1][j+p] );
        }
    }


}