public static int first ( int n ) {
  int a = n ;
  int c = 1 ;
  while ( a != 0 ) {
    a /= 10 ;
    c = c * 10 ;
  }
  c = c / 10 ;
  int fi = n / c ;
  return fi ;
}

public static int first ( int n ) { int a = n ; int c = 1 ; while ( a != 0 ) { a /= 10 ; c = c * 10 ; } c = c / 10 ; int fi = n / c ; return fi ; }
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