public static void main ( String [ ] args ) throws Exception {
  Scanner sc = new Scanner ( System . in ) ;
  int n = sc . nextInt ( ) ;
  int d = ( int ) Math . floor ( Math . log10 ( n ) + 1 ) ;
  if ( n < 9 ) System . out . println ( n ) ;
  else {
    double i = 1 ;
    long sum = 0 , res = 0 ;
    while ( i < d ) {
      long k = ( long ) ( 9 * Math . pow ( 10 , i - 1 ) ) ;
      sum = sum + ( k ) ;
      res = ( long ) ( res + ( k * i ) ) ;
      i ++ ;
    }
    res = ( long ) ( res + ( ( n - sum ) * i ) ) ;
    System . out . println ( res ) ;
  }
}

public static void main ( String [ ] args ) throws Exception { Scanner sc = new Scanner ( System . in ) ; int n = sc . nextInt ( ) ; int d = ( int ) Math . floor ( Math . log10 ( n ) + 1 ) ; if ( n < 9 ) System . out . println ( n ) ; else { double i = 1 ; long sum = 0 , res = 0 ; while ( i < d ) { long k = ( long ) ( 9 * Math . pow ( 10 , i - 1 ) ) ; sum = sum + ( k ) ; res = ( long ) ( res + ( k * i ) ) ; i ++ ; } res = ( long ) ( res + ( ( n - sum ) * i ) ) ; System . out . println ( res ) ; } }
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