#include<iostream>
#include<cstdio>
#include<cstring>
#define ull unsigned long long
using namespace std;

ull n,br;
ull used[10];
ull ans,a,b;


ull check(ull x)
{
    memset(used,0,sizeof(used));
    ull i;
    while(x)
    {
        used[x%10]++;
        x/=10;
    }
    for(i=0;i<10;i++)
    if(used[i])
    {
        if((i&1)&&(used[i]&1))return 0;
        if((i&1)==0&&(used[i]&1)==0)return 0;
    }
    return 1;
}

int main()
{
    cin>>a>>b;
    for(ull i=a;i<=b;i++)
     ans+=check(i);
    cout<<ans<<"\n";
}
