#include <iostream>
#include <stdio.h>
#include <set>
using namespace std;

char number[21];
set<string> myset;

int main()
{
    int i,j,in;
    string newnum;

    scanf("%s",number+1);

    for (i=2;i<=9;i++)
    {
        for (j=0;j<=9;j++)
        {
            newnum.clear();
            for (in=1;in<=i;in++)
            {
                newnum.push_back( number[in] );
            }
            newnum.push_back( (char)(j+'0') );
            for (in=i+1;in<=9;in++)
            {
                newnum.push_back( number[in] );
            }

            myset.insert(newnum);
        }
    }

    printf("%d\n",(int)myset.size());

    return 0;
}