#include <iostream>
#include <cstring>
#include <string>
#include <cstdio>
#include <cmath>
#include <ctime>
#include <algorithm>
#include <queue>
#include <map>
#define FOP freopen("in","r",stdin)
#define inf 0x3f3f3f3f
#define ll __int64
#define eps 1e-8
using namespace std;
int f[8][10];
int digit[9];
int lenmethod( int num )
{
int len = 0;
while( num )
{
++len;
num = num / 10;
}
return len;
}
void digitmethod( int n , int len )
{
memset( digit , 0 , sizeof digit );
for( int i = 1 ; i <= len ; i++ )
{
digit[i] = n % 10;
n = n / 10;
}
return;
}
void Init()
{
int i,j,k;
memset( f , 0 , sizeof f );
f[0][0] = 1;
for( i = 1 ; i <= 7 ; i++ )
{
for( j = 0 ; j < 10 ; j++ )
{
for( k = 0 ; k < 10 ; k++ )
{
if( !(k==2&&j==6) && j!=4 )
f[i][j] += f[i-1][k];
}
}
}
return;
}
int solve( int n )
{
int ans,len,i,j;
ans = 0;
len = lenmethod(n);
digitmethod(n,len);
for( i = len ; i >= 1 ; i-- )
{
for( j = 0 ; j < digit[i] ; j++ )
{
if( j != 4 && !( j==2 && digit[i+1]==6 ) )
ans += f[i][j];
}
if( digit[i]==4 || ( digit[i]==2 && digit[i+1]==6) )
break;
}
return ans;
}
int main()
{
int l,r;
Init();
while( scanf( "%d%d" , &l , &r ) )
{
if( l == 0 && r == 0 ) break;
printf( "%d\n" , solve(r+1) - solve(l) );
}
return 0;
}