#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
const int N=1e6;
int RN(int a)
{	
	int months[13]={0,31,29,31,30,31,30,31,31,30,31,30,31};
	int month=a/100%100,day=a%100;
	if(month<1||month>12) return 0;
	if(day<1||day>months[month]) return 0;
	return 1;
}
int HW(int n)
{
	int sum1=0,k=n;
	while(k)
	{
		sum1=sum1*10+k%10;
		k/=10;
	}
	if(sum1==n) return 1;
	return 0; 
}
int main()
{
	int d1,d2,sum=0;
	cin>>d1>>d2;
	for(int i=d1;i<=d2;i++)
	{
		if(HW(i)==1&&RN(i)==1)
			sum++;
	}
	cout<<sum;
	return 0;
}