import java.util.Scanner; public class Main{ public static void main(String[] args){ Scanner cs = new Scanner(System.in); while(cs.hasNext()){ long n = cs.nextLong(); if(n<1 || n>100000000){ n = 20123; } int x; String str; int i ; int k; int count = 0; for(i=1 ; i<n+1 ; i++){ str = "" + i ; k = str.length(); for(int j =0;j<k;j++){ if(str.charAt(j) == '1' || str.charAt(j) == '2') count = count + 1;