Cod sursa(job #440341)

Utilizator OdinSandu Bogdan-Mihai Odin Data 12 aprilie 2010 00:01:07
Problema Range minimum query Scor 90
Compilator cpp Status done
Runda Arhiva educationala Marime 0.71 kb
#include<stdio.h>
int v[100005],M[100005][20],n,m,i,x,y,j,lg[100005];
void process()
{
	for(i=0;i<n;i++)
		M[i][0]=i;
	for(i=2;i<=n;i++)
		lg[i]=lg[i/2]+1;
	for(j=1;(1<<j)<=n;j++)
		for(i=0;i+(1<<j)-1<n;i++)
			if(v[M[i][j-1]]<=v[M[i+(1<<(j-1))][j-1]])
				M[i][j]=M[i][j-1];
			else M[i][j]=M[i+(1<<(j-1))][j-1];
}
int rmq(int i, int j)
{
	int k=lg[j-i+1];
	if(v[M[i][k]]<=v[M[j-(1<<k)+1][k]])
		return v[M[i][k]];
	return v[M[j-(1<<k)+1][k]];
}
int main()
{
	freopen("rmq.in","r",stdin);
	freopen("rmq.out","w",stdout);
	scanf("%d %d",&n,&m);
	for(i=0;i<n;i++)
		scanf("%d",&v[i]);
	process();
	for(i=0;i<m;i++)
	{
		scanf("%d %d",&x,&y);
		printf("%d\n",rmq(x-1,y-1));
	}
	return 0;
}