public static void main ( String [ ] args ) {
  FastScanner input = new FastScanner ( ) ;
  int n = input . nextInt ( ) ;
  int a [ ] = new int [ n ] ;
  for ( int i = 0 ;
  i < n ;
  i ++ ) {
    a [ i ] = input . nextInt ( ) ;
  }
  int ans = 1 ;
  int min = Integer . MAX_VALUE ;
  int max = Integer . MIN_VALUE ;
  int nextMinIndex = 0 ;
  int nextMaxIndex = 0 ;
  int count = 0 ;
  for ( int i = 0 ;
  i < n ;
  i ++ ) {
    if ( a [ i ] <= min ) {
      nextMinIndex = i ;
      min = a [ i ] ;
    }
    if ( a [ i ] >= max ) {
      nextMaxIndex = i ;
      max = Math . max ( max , a [ i ] ) ;
    }
    if ( Math . abs ( max - min ) <= 1 ) {
      count ++ ;
      ans = Math . max ( ans , count ) ;
    }
    else {
      count = 0 ;
      min = Integer . MAX_VALUE ;
      max = Integer . MIN_VALUE ;
      i = Math . min ( nextMaxIndex , nextMinIndex ) ;
    }
  }
  System . out . println ( ans ) ;
}

public static void main ( String [ ] args ) { FastScanner input = new FastScanner ( ) ; int n = input . nextInt ( ) ; int a [ ] = new int [ n ] ; for ( int i = 0 ; i < n ; i ++ ) { a [ i ] = input . nextInt ( ) ; } int ans = 1 ; int min = Integer . MAX_VALUE ; int max = Integer . MIN_VALUE ; int nextMinIndex = 0 ; int nextMaxIndex = 0 ; int count = 0 ; for ( int i = 0 ; i < n ; i ++ ) { if ( a [ i ] <= min ) { nextMinIndex = i ; min = a [ i ] ; } if ( a [ i ] >= max ) { nextMaxIndex = i ; max = Math . max ( max , a [ i ] ) ; } if ( Math . abs ( max - min ) <= 1 ) { count ++ ; ans = Math . max ( ans , count ) ; } else { count = 0 ; min = Integer . MAX_VALUE ; max = Integer . MIN_VALUE ; i = Math . min ( nextMaxIndex , nextMinIndex ) ; } } 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))) body: (block (local_variable_declaration type: (type_identifier) declarator: (variable_declarator name: (identifier) value: (object_creation_expression type: (type_identifier) arguments: (argument_list)))) (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: (integral_type) declarator: (variable_declarator name: (identifier) dimensions: (dimensions) 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: (block (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: (field_access object: (identifier) field: (identifier)))) (local_variable_declaration type: (integral_type) declarator: (variable_declarator name: (identifier) value: (field_access object: (identifier) field: (identifier)))) (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))) (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: (block (if_statement condition: (parenthesized_expression (binary_expression left: (array_access array: (identifier) index: (identifier)) right: (identifier))) consequence: (block (expression_statement (assignment_expression left: (identifier) right: (identifier))) (expression_statement (assignment_expression left: (identifier) right: (array_access array: (identifier) index: (identifier)))))) (if_statement condition: (parenthesized_expression (binary_expression left: (array_access array: (identifier) index: (identifier)) right: (identifier))) consequence: (block (expression_statement (assignment_expression left: (identifier) right: (identifier))) (expression_statement (assignment_expression left: (identifier) right: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (identifier) (array_access array: (identifier) index: (identifier)))))))) (if_statement condition: (parenthesized_expression (binary_expression left: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (binary_expression left: (identifier) right: (identifier)))) right: (decimal_integer_literal))) consequence: (block (expression_statement (update_expression (identifier))) (expression_statement (assignment_expression left: (identifier) right: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (identifier) (identifier)))))) alternative: (block (expression_statement (assignment_expression left: (identifier) right: (decimal_integer_literal))) (expression_statement (assignment_expression left: (identifier) right: (field_access object: (identifier) field: (identifier)))) (expression_statement (assignment_expression left: (identifier) right: (field_access object: (identifier) field: (identifier)))) (expression_statement (assignment_expression left: (identifier) right: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (identifier) (identifier))))))))) (expression_statement (method_invocation object: (field_access object: (identifier) field: (identifier)) name: (identifier) arguments: (argument_list (identifier))))))