#include <bits/stdc++.h>
using namespace std;
using ll = long long;
int main () {
	ll N;
	cin >> N;
	unordered_set<ll> st;
	int n = to_string(N).size();
	ll b = 1;
	for (int i = 0; i <= n; i ++) {
		for (ll a = 0; a < 10; a ++) {
			ll x = (N / b) * (b * 10) + a * b + N % b;
			if (x != N) {
				st.insert(x);
			}
		}
	}
	cout << st.size() << endl;
}