public static void main ( String [ ] args ) {
  Scanner in = new Scanner ( System . in ) ;
  int n , x , y , z , Sum_X = 0 , Sum_Y = 0 , Sum_Z = 0 ;
  n = in . nextInt ( ) ;
  for ( int i = 0 ;
  i < n ;
  i ++ ) {
    x = in . nextInt ( ) ;
    y = in . nextInt ( ) ;
    z = in . nextInt ( ) ;
    Sum_X = Sum_X + x ;
    Sum_Y = Sum_Y + y ;
    Sum_Z = Sum_Z + z ;
  }
  if ( Sum_X == 0 && Sum_Y == 0 && Sum_Z == 0 ) System . out . println ( "YES" ) ;
  else System . out . println ( "NO" ) ;
}

public static void main ( String [ ] args ) { Scanner in = new Scanner ( System . in ) ; int n , x , y , z , Sum_X = 0 , Sum_Y = 0 , Sum_Z = 0 ; n = in . nextInt ( ) ; for ( int i = 0 ; i < n ; i ++ ) { x = in . nextInt ( ) ; y = in . nextInt ( ) ; z = in . nextInt ( ) ; Sum_X = Sum_X + x ; Sum_Y = Sum_Y + y ; Sum_Z = Sum_Z + z ; } if ( Sum_X == 0 && Sum_Y == 0 && Sum_Z == 0 ) 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)) declarator: (variable_declarator name: (identifier)) declarator: (variable_declarator name: (identifier)) declarator: (variable_declarator name: (identifier)) declarator: (variable_declarator name: (identifier) value: (decimal_integer_literal)) declarator: (variable_declarator name: (identifier) value: (decimal_integer_literal)) declarator: (variable_declarator name: (identifier) value: (decimal_integer_literal))) (expression_statement (assignment_expression left: (identifier) right: (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 (expression_statement (assignment_expression left: (identifier) right: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list)))) (expression_statement (assignment_expression left: (identifier) right: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list)))) (expression_statement (assignment_expression left: (identifier) right: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list)))) (expression_statement (assignment_expression left: (identifier) right: (binary_expression left: (identifier) right: (identifier)))) (expression_statement (assignment_expression left: (identifier) right: (binary_expression left: (identifier) right: (identifier)))) (expression_statement (assignment_expression left: (identifier) right: (binary_expression left: (identifier) right: (identifier)))))) (if_statement condition: (parenthesized_expression (binary_expression left: (binary_expression left: (binary_expression left: (identifier) right: (decimal_integer_literal)) right: (binary_expression left: (identifier) right: (decimal_integer_literal))) right: (binary_expression left: (identifier) right: (decimal_integer_literal)))) consequence: (expression_statement (method_invocation object: (field_access object: (identifier) field: (identifier)) name: (identifier) arguments: (argument_list (string_literal)))) alternative: (expression_statement (method_invocation object: (field_access object: (identifier) field: (identifier)) name: (identifier) arguments: (argument_list (string_literal)))))))