Cod sursa(job #528341)

Utilizator BlaugranasEnal Gemaledin Blaugranas Data 2 februarie 2011 17:14:53
Problema Range minimum query Scor 90
Compilator cpp Status done
Runda Arhiva educationala Marime 0.91 kb
#include<stdio.h>
#define N 100001
long n,m,a[N],i,j,x,b[N][18],y,k,p;

int caut(long x)
{int i,step=16;
for(i=0;step!=0;step>>=1)
if(1<<(i+step)<=x)
      i+=step;
return i;}

void rmq(long b[N][18],long a[N],long n)
{long i,j;
for(i=0;i<n;i++)
      b[i][0]=i;
for(j=1;(1<<j)<=n;j++)
      {for(i=0;i+(1<<j)-1<n;i++)
      if(a[b[i][j-1]]<a[b[i+(1<<(j-1))][j-1]])
             b[i][j]=b[i][j-1];
      else
             b[i][j]=b[i+(1<<(j-1))][j-1];}}

int main()
{freopen("rmq.in","r",stdin);
freopen("rmq.out","w",stdout);
scanf("%ld%ld\n",&n,&m);
for(i=0;i<n;i++)
      scanf("%ld\n",&a[i]);
rmq(b,a,n);
for(j=0;j<m;j++)
      {scanf("%ld%ld\n",&x,&y);
      x--;
      y--;
      k=caut(y-x+1);
      if(a[b[x][k]]<=a[b[y-(1<<k)+1][k]])
              printf("%ld\n",a[b[x][k]]);
      else
              printf("%ld\n",a[b[y-(1<<k)+1][k]]);}
fclose(stdin);
fclose(stdout);
return 0;}