#include<stdio.h>
#include<string.h>
#define max 1000000+10
int luck[max]; //储存第i个数是第几个吉利数 
int main()
{
	int n,m,j,i,l,sum;
	char s[15];
	memset(luck,0,sizeof(luck));
	for(i=1;i<max;i++)
	{
		l=sprintf(s,"%d",i);
		sum=0;
		for(j=0;j<l;j++)
		{
			if(s[j]==‘4‘||(s[j]==‘6‘&&s[j+1]==‘2‘))//判断一个数是否为不幸运数 
			{
				luck[i]=luck[i-1];
				break;
			}
			else
			luck[i]=luck[i-1]+1;
		}
	}
	while(scanf("%d%d",&n,&m)&&n!=0&&m!=0)
	{
		printf("%d\n",luck[m]-luck[n-1]);
	}
	return 0;
}