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#include <iostream>
#include <string>
using namespace std;

int main(){

        long long unsigned int n, result, prev,tmp;
        cin >> n;
        string s = to_string(n);

        prev = 1;
        result = s[s.size()-1] - '0' + 1;

        for(int i=s.size() - 2; i >=0; i-- ){
                tmp = result * (s[i] - '0' + 1);
                if( s[i] == '1' && s[i+1] < '9' ){
                   tmp += prev * (9- s[i+1] + '0');
                }
                prev = result;
                result = tmp;
        }
        cout << result;
        return 0;
}