public static void main ( String [ ] args ) {
  Scanner sc = new Scanner ( System . in ) ;
  int n = sc . nextInt ( ) ;
  lists = new ArrayList [ n + 1 ] ;
  for ( int i = 1 ;
  i <= n ;
  i ++ ) {
    lists [ i ] = new ArrayList < Route > ( ) ;
  }
  for ( int i = 1 ;
  i < n ;
  i ++ ) {
    int a = sc . nextInt ( ) ;
    int b = sc . nextInt ( ) ;
    int c = sc . nextInt ( ) ;
    lists [ a ] . add ( new Route ( b , c ) ) ;
    lists [ b ] . add ( new Route ( a , c ) ) ;
  }
  costs = new long [ n + 1 ] ;
  Arrays . fill ( costs , - 1 ) ;
  int q = sc . nextInt ( ) ;
  int k = sc . nextInt ( ) ;
  setCost ( 0 , k ) ;
  StringBuilder sb = new StringBuilder ( ) ;
  for ( int i = 0 ;
  i < q ;
  i ++ ) {
    int x = sc . nextInt ( ) ;
    int y = sc . nextInt ( ) ;
    sb . append ( costs [ x ] + costs [ y ] ) . append ( "\n" ) ;
  }
  System . out . print ( sb ) ;
}

public static void main ( String [ ] args ) { Scanner sc = new Scanner ( System . in ) ; int n = sc . nextInt ( ) ; lists = new ArrayList [ n + 1 ] ; for ( int i = 1 ; i <= n ; i ++ ) { lists [ i ] = new ArrayList < Route > ( ) ; } for ( int i = 1 ; i < n ; i ++ ) { int a = sc . nextInt ( ) ; int b = sc . nextInt ( ) ; int c = sc . nextInt ( ) ; lists [ a ] . add ( new Route ( b , c ) ) ; lists [ b ] . add ( new Route ( a , c ) ) ; } costs = new long [ n + 1 ] ; Arrays . fill ( costs , - 1 ) ; int q = sc . nextInt ( ) ; int k = sc . nextInt ( ) ; setCost ( 0 , k ) ; StringBuilder sb = new StringBuilder ( ) ; for ( int i = 0 ; i < q ; i ++ ) { int x = sc . nextInt ( ) ; int y = sc . nextInt ( ) ; sb . append ( costs [ x ] + costs [ y ] ) . append ( " \n " ) ; } System . out . print ( sb ) ; }
(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 (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)))) (expression_statement (assignment_expression left: (identifier) right: (array_creation_expression type: (type_identifier) dimensions: (dimensions_expr (binary_expression left: (identifier) right: (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 (expression_statement (assignment_expression left: (array_access array: (identifier) index: (identifier)) right: (object_creation_expression type: (generic_type (type_identifier) (type_arguments (type_identifier))) arguments: (argument_list)))))) (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 (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) value: (method_invocation object: (identifier) name: (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)))) (expression_statement (method_invocation object: (array_access array: (identifier) index: (identifier)) name: (identifier) arguments: (argument_list (object_creation_expression type: (type_identifier) arguments: (argument_list (identifier) (identifier)))))) (expression_statement (method_invocation object: (array_access array: (identifier) index: (identifier)) name: (identifier) arguments: (argument_list (object_creation_expression type: (type_identifier) arguments: (argument_list (identifier) (identifier)))))))) (expression_statement (assignment_expression left: (identifier) right: (array_creation_expression type: (integral_type) dimensions: (dimensions_expr (binary_expression left: (identifier) right: (decimal_integer_literal)))))) (expression_statement (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (identifier) (unary_expression operand: (decimal_integer_literal))))) (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) value: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list)))) (expression_statement (method_invocation name: (identifier) arguments: (argument_list (decimal_integer_literal) (identifier)))) (local_variable_declaration type: (type_identifier) declarator: (variable_declarator name: (identifier) value: (object_creation_expression type: (type_identifier) arguments: (argument_list)))) (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 (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) value: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list)))) (expression_statement (method_invocation object: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (binary_expression left: (array_access array: (identifier) index: (identifier)) right: (array_access array: (identifier) index: (identifier))))) name: (identifier) arguments: (argument_list (string_literal)))))) (expression_statement (method_invocation object: (field_access object: (identifier) field: (identifier)) name: (identifier) arguments: (argument_list (identifier))))))