Cod sursa(job #626792)

Utilizator ContraPunctContrapunct ContraPunct Data 28 octombrie 2011 12:04:14
Problema Range minimum query Scor 40
Compilator cpp Status done
Runda Arhiva educationala Marime 0.91 kb
#include <stdio.h>
#define NMAX 100002
using namespace std;

long int rmq[20][NMAX];
long int n,m,ul;
long int lg[NMAX];
long int p2[NMAX];
long int a[NMAX];

long int min(long int a, long int b)
{
if(a<b)
	return a;
return b;
}

int main()
{
	freopen("rmq.in","r",stdin);
	freopen("rmq.out","w",stdout);
	int i;

	scanf("%ld %ld",&n,&m);

	for (i=1;i<=n;i++)
		scanf("%ld ",&a[i]);

	lg[1]=0;
	for (i=2;i<=n;i++)
		lg[i]=lg[i/2]+1;
	p2[0]=1;
	for(i=1;p2[ul]<=n;i++)
		p2[++ul]=p2[ul-1]<<1;
	for (i=1;i<=n;i++)
		rmq[0][i]=a[i];
	int j,l;
	for (i=1; (1 << i) <=n;i++)
		for (j=1;j <= n - p2[i]+1;j++)
		{
		l=p2[i-1];
		if(rmq[i-1][j] < rmq[i-1][j+l])
			rmq[i][j]= rmq[i-1][j];
		else 
			rmq[i][j]= rmq[i-1][j+l];
		}
	long int x,y,diff,sh;
	
	for (i=1;i<=m;i++)
	{
		scanf("%ld %ld",&x,&y);
		
		diff=y-x+1;
		l=lg[diff];
		sh=diff - (p2[l]);
		printf("%ld\n",min(rmq[l][x],rmq[l][x+sh]) );
	}	
	return 0;
}