public static void main ( String [ ] args ) throws IOException {
  Scanner sc = new Scanner ( System . in ) ;
  int n = sc . nextInt ( ) ;
  int [ ] a = new int [ n ] ;
  for ( int i = 0 ;
  i < n ;
  i ++ ) a [ i ] = sc . nextInt ( ) ;
  int start = 0 ;
  int end = 0 ;
  int v = 0 ;
  long s = 0 ;
  long ans = 0 ;
  boolean f = true ;
  while ( end < n ) {
    if ( f ) {
      s += a [ end ] ;
      v ^= a [ end ] ;
    }
    if ( s == v ) {
      f = true ;
      end ++ ;
    }
    else {
      f = false ;
      long len = end - start ;
      ans += len ;
      s -= a [ start ] ;
      v ^= a [ start ] ;
      start ++ ;
    }
  }
  if ( f ) {
    long len = ( end - start ) ;
    ans += ( len ) * ( len - 1 ) / 2 ;
    ans += len ;
  }
  System . out . println ( ans ) ;
}

public static void main ( String [ ] args ) throws IOException { Scanner sc = new Scanner ( System . in ) ; int n = sc . nextInt ( ) ; int [ ] a = new int [ n ] ; for ( int i = 0 ; i < n ; i ++ ) a [ i ] = sc . nextInt ( ) ; int start = 0 ; int end = 0 ; int v = 0 ; long s = 0 ; long ans = 0 ; boolean f = true ; while ( end < n ) { if ( f ) { s += a [ end ] ; v ^= a [ end ] ; } if ( s == v ) { f = true ; end ++ ; } else { f = false ; long len = end - start ; ans += len ; s -= a [ start ] ; v ^= a [ start ] ; start ++ ; } } if ( f ) { long len = ( end - start ) ; ans += ( len ) * ( len - 1 ) / 2 ; ans += len ; } System . out . println ( ans ) ; }
(method_declaration (modifiers) type: (void_type) name: (identifier) parameters: (formal_parameters (formal_parameter type: (array_type element: (type_identifier) dimensions: (dimensions)) name: (identifier))) (throws (type_identifier)) body: (block (local_variable_declaration type: (type_identifier) declarator: (variable_declarator name: (identifier) value: (object_creation_expression type: (type_identifier) arguments: (argument_list (field_access object: (identifier) field: (identifier)))))) (local_variable_declaration type: (integral_type) declarator: (variable_declarator name: (identifier) value: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list)))) (local_variable_declaration type: (array_type element: (integral_type) dimensions: (dimensions)) declarator: (variable_declarator name: (identifier) value: (array_creation_expression type: (integral_type) dimensions: (dimensions_expr (identifier))))) (for_statement init: (local_variable_declaration type: (integral_type) declarator: (variable_declarator name: (identifier) value: (decimal_integer_literal))) condition: (binary_expression left: (identifier) right: (identifier)) update: (update_expression (identifier)) body: (expression_statement (assignment_expression left: (array_access array: (identifier) index: (identifier)) right: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list))))) (local_variable_declaration type: (integral_type) declarator: (variable_declarator name: (identifier) value: (decimal_integer_literal))) (local_variable_declaration type: (integral_type) declarator: (variable_declarator name: (identifier) value: (decimal_integer_literal))) (local_variable_declaration type: (integral_type) declarator: (variable_declarator name: (identifier) value: (decimal_integer_literal))) (local_variable_declaration type: (integral_type) declarator: (variable_declarator name: (identifier) value: (decimal_integer_literal))) (local_variable_declaration type: (integral_type) declarator: (variable_declarator name: (identifier) value: (decimal_integer_literal))) (local_variable_declaration type: (boolean_type) declarator: (variable_declarator name: (identifier) value: (true))) (while_statement condition: (parenthesized_expression (binary_expression left: (identifier) right: (identifier))) body: (block (if_statement condition: (parenthesized_expression (identifier)) consequence: (block (expression_statement (assignment_expression left: (identifier) right: (array_access array: (identifier) index: (identifier)))) (expression_statement (assignment_expression left: (identifier) right: (array_access array: (identifier) index: (identifier)))))) (if_statement condition: (parenthesized_expression (binary_expression left: (identifier) right: (identifier))) consequence: (block (expression_statement (assignment_expression left: (identifier) right: (true))) (expression_statement (update_expression (identifier)))) alternative: (block (expression_statement (assignment_expression left: (identifier) right: (false))) (local_variable_declaration type: (integral_type) declarator: (variable_declarator name: (identifier) value: (binary_expression left: (identifier) right: (identifier)))) (expression_statement (assignment_expression left: (identifier) right: (identifier))) (expression_statement (assignment_expression left: (identifier) right: (array_access array: (identifier) index: (identifier)))) (expression_statement (assignment_expression left: (identifier) right: (array_access array: (identifier) index: (identifier)))) (expression_statement (update_expression (identifier))))))) (if_statement condition: (parenthesized_expression (identifier)) consequence: (block (local_variable_declaration type: (integral_type) declarator: (variable_declarator name: (identifier) value: (parenthesized_expression (binary_expression left: (identifier) right: (identifier))))) (expression_statement (assignment_expression left: (identifier) right: (binary_expression left: (binary_expression left: (parenthesized_expression (identifier)) right: (parenthesized_expression (binary_expression left: (identifier) right: (decimal_integer_literal)))) right: (decimal_integer_literal)))) (expression_statement (assignment_expression left: (identifier) right: (identifier))))) (expression_statement (method_invocation object: (field_access object: (identifier) field: (identifier)) name: (identifier) arguments: (argument_list (identifier))))))