//Code by Patcas Csaba

#include <vector>
#include <string> 
#include <set> 
#include <map> 
#include <queue> 
#include <bitset> 
#include <stack>
#include <list>

#include <numeric> 
#include <algorithm> 

#include <cstdio>
#include <fstream>
#include <iostream> 
#include <sstream> 
#include <iomanip>

#include <cctype>
#include <cmath> 
#include <ctime>
#include <cassert>

using namespace std;

#define LL long long
#define PII pair <int, int>
#define VB vector <bool>
#define VI vector <int>
#define VD vector <double>
#define VS vector <string>
#define VPII vector <pair <int, int> >
#define VVI vector < VI >
#define VVB vector < VB >

#define FORN(i, n) for(int i = 0; i < (n); ++i)
#define FOR(i, a, b) for(int i = (a); i <= (b); ++i)
#define FORD(i, a, b) for(int i = (a); i >= (b); --i)
#define FORI(it, X) for(__typeof((X).begin()) it = (X).begin(); it !=(X).end(); ++it) 
#define REPEAT do{ 
#define UNTIL(x) }while(!(x)); 

#define SZ size()
#define BG begin() 
#define EN end() 
#define CL clear()
#define X first
#define Y second
#define RS resize
#define PB push_back
#define MP make_pair
#define ALL(x) x.begin(), x.end()

#define IN_FILE "a.in"
#define OUT_FILE "a.out"

LL a, b;
vector<LL> ans(20), part(20);

int main()
{
	//Read data
	//freopen(IN_FILE, "r", stdin);
	//freopen(OUT_FILE, "w", stdout);

	//Solve
	cin >> a >> b;

	if (a >= 10) 
	{
		cout << 0;
		return 0;
	}

	int nrDig = 10 - a;
	ans[0] = 1;
	ans[1] = nrDig;
	part[1] = nrDig;
	FOR(i, 2, 18) 
	{
		ans[i] = ans[i - 1] * nrDig;
		part[i] = part[i - 1] + ans[i];
	}

	VI digits;
	LL aux = b;
	while (aux)
	{
		digits.PB(aux % 10);
		aux /= 10;
	}
	reverse(ALL(digits));

	int m = digits.SZ;

	LL sol = part[m - 1];

	FOR(i, 0, m - 1)
	{
		if (digits[i] >= a)
		{
			sol += (digits[i] - a) * ans[m - i - 1];
			if (i == (m - 1)) ++sol;
		}
		else break;
	}

	//Write data
	cout << sol << endl;

	return 0;
}