#include <iostream>

using namespace std;

bool interesting(long long int a)
{
    long long int b = a*9;
    int sb = 0, sa = 0;
    
    while(a)
    {
        sa += a%10;
        a /= 10;
    }
    while(b)
    {
        sb += b%10;
        b /= 10;
    }
    if(sa == sb)return true;
    else return false;
}

int main()
{
    long long int a, b;
    int interes = 0;
    cin >> a >> b;
    b++;
    a = a - a%9 + 9;
    for(;a < b;a += 9)if(interesting(a))interes++;
    cout << interes << endl;
    return 0;
}