static String commonPrefix ( String arr [ ] , int n ) {
  String prefix = arr [ 0 ] ;
  for ( int i = 1 ;
  i <= n - 1 ;
  i ++ ) {
    prefix = commonPrefixUtil ( prefix , arr [ i ] ) ;
  }
  return ( prefix ) ;
}

static String commonPrefix ( String arr [ ] , int n ) { String prefix = arr [ 0 ] ; for ( int i = 1 ; i <= n - 1 ; i ++ ) { prefix = commonPrefixUtil ( prefix , arr [ i ] ) ; } return ( prefix ) ; }
(method_declaration (modifiers) type: (type_identifier) name: (identifier) parameters: (formal_parameters (formal_parameter type: (type_identifier) name: (identifier) dimensions: (dimensions)) (formal_parameter type: (integral_type) name: (identifier))) body: (block (local_variable_declaration type: (type_identifier) declarator: (variable_declarator name: (identifier) value: (array_access array: (identifier) index: (decimal_integer_literal)))) (for_statement init: (local_variable_declaration type: (integral_type) declarator: (variable_declarator name: (identifier) value: (decimal_integer_literal))) condition: (binary_expression left: (identifier) right: (binary_expression left: (identifier) right: (decimal_integer_literal))) update: (update_expression (identifier)) body: (block (expression_statement (assignment_expression left: (identifier) right: (method_invocation name: (identifier) arguments: (argument_list (identifier) (array_access array: (identifier) index: (identifier)))))))) (return_statement (parenthesized_expression (identifier)))))