public static void main ( String [ ] args ) {
  Scanner tin = new Scanner ( System . in ) ;
  int t = tin . nextInt ( ) ;
  for ( int x = 0 ;
  x < t ;
  x ++ ) {
    boolean rhj = true ;
    long a = tin . nextLong ( ) ;
    long b = tin . nextLong ( ) ;
    long y = a + b ;
    for ( int z = 2 ;
    z <= Math . sqrt ( y ) ;
    z ++ ) {
      if ( y % z == 0 ) {
        rhj = false ;
      }
    }
    if ( rhj && a - b == 1 ) {
      System . out . println ( "Yes" ) ;
    }
    else {
      System . out . println ( "No" ) ;
    }
  }
}

public static void main ( String [ ] args ) { Scanner tin = new Scanner ( System . in ) ; int t = tin . nextInt ( ) ; for ( int x = 0 ; x < t ; x ++ ) { boolean rhj = true ; long a = tin . nextLong ( ) ; long b = tin . nextLong ( ) ; long y = a + b ; for ( int z = 2 ; z <= Math . sqrt ( y ) ; z ++ ) { if ( y % z == 0 ) { rhj = false ; } } if ( rhj && a - b == 1 ) { System . out . println ( " Yes " ) ; } else { System . out . println ( " No " ) ; } } }
(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)))) (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: (boolean_type) declarator: (variable_declarator name: (identifier) value: (true))) (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: (binary_expression left: (identifier) right: (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: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (identifier)))) update: (update_expression (identifier)) body: (block (if_statement condition: (parenthesized_expression (binary_expression left: (binary_expression left: (identifier) right: (identifier)) right: (decimal_integer_literal))) consequence: (block (expression_statement (assignment_expression left: (identifier) right: (false))))))) (if_statement condition: (parenthesized_expression (binary_expression left: (identifier) right: (binary_expression left: (binary_expression left: (identifier) right: (identifier)) right: (decimal_integer_literal)))) consequence: (block (expression_statement (method_invocation object: (field_access object: (identifier) field: (identifier)) name: (identifier) arguments: (argument_list (string_literal))))) alternative: (block (expression_statement (method_invocation object: (field_access object: (identifier) field: (identifier)) name: (identifier) arguments: (argument_list (string_literal))))))))))