Uva 10533 solution in C (I have use sieve algorithm here) :)

#include<stdio.h>
#include <math.h>
#define MAX 1000001
int digit_primes [MAX ] ;
char prime [ MAX ];
void algo ()
 {
int i , j , x , n , p ;
 n = MAX ;
 x = sqrt ( n) ;
 prime [ 0 ] = prime [ 1 ] =
1 ;
for ( i = 4 ; i <=n ; i += 2 ){
prime [ i ] = 1 ;
}
for ( i = 3 ; i <= x ; i += 2 )
{
if( prime [ i ] == 0 ){
for ( j = i + i; j <= n ; j +=
i ){
 prime [ j ] = 1 ;
}
}
 }
 return;
}
int sum ( int n ){
int sum = 0 , r ;
while ( n != 0 ){
 r = n % 10;
n /= 10;
sum += r ;
 }
 return sum ;
}
 int main ()
{
int a , b , t , i , count = 0 ;
algo() ;
for ( i = 0 ; i <= 1000000 ; i
++ )
{
if( prime [ i ]== 0 && prime[sum (i )] == 0 )
 count ++;
digit_primes [ i ] = count ;
 }
while ( scanf ( " %d " , & t )
&& t > 0 ){
while ( t -- ){
 scanf ( " %d %d " , & a , &b ) ;
 printf( "%d \n " ,
digit_primes [ b ]- digit_primes[ a - 1 ]) ;
 }
 }
 return 0 ;
 }