public static void main ( String [ ] args ) {
  Scanner sc = new Scanner ( System . in ) ;
  int n = sc . nextInt ( ) ;
  int in = sc . nextInt ( ) ;
  int op = 7 - in ;
  boolean works = false ;
  while ( n -- > 0 ) {
    int a = sc . nextInt ( ) ;
    int b = sc . nextInt ( ) ;
    if ( a == in || a == op ) works = true ;
    if ( b == in || b == op ) works = true ;
  }
  System . out . println ( works ? "NO" : "YES" ) ;
}

public static void main ( String [ ] args ) { Scanner sc = new Scanner ( System . in ) ; int n = sc . nextInt ( ) ; int in = sc . nextInt ( ) ; int op = 7 - in ; boolean works = false ; while ( n -- > 0 ) { int a = sc . nextInt ( ) ; int b = sc . nextInt ( ) ; if ( a == in || a == op ) works = true ; if ( b == in || b == op ) works = true ; } System . out . println ( works ? " NO " : " YES " ) ; }
(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)))) (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: (decimal_integer_literal) right: (identifier)))) (local_variable_declaration type: (boolean_type) declarator: (variable_declarator name: (identifier) value: (false))) (while_statement condition: (parenthesized_expression (binary_expression left: (update_expression (identifier)) right: (decimal_integer_literal))) 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)))) (if_statement condition: (parenthesized_expression (binary_expression left: (binary_expression left: (identifier) right: (identifier)) right: (binary_expression left: (identifier) right: (identifier)))) consequence: (expression_statement (assignment_expression left: (identifier) right: (true)))) (if_statement condition: (parenthesized_expression (binary_expression left: (binary_expression left: (identifier) right: (identifier)) right: (binary_expression left: (identifier) right: (identifier)))) consequence: (expression_statement (assignment_expression left: (identifier) right: (true)))))) (expression_statement (method_invocation object: (field_access object: (identifier) field: (identifier)) name: (identifier) arguments: (argument_list (ternary_expression condition: (identifier) consequence: (string_literal) alternative: (string_literal)))))))