public static void main ( String [ ] args ) throws Exception {
  int n = sc . nextInt ( ) , count = 0 , x = 0 , y = 0 , temp = 0 ;
  for ( int i = 0 ;
  i < n ;
  i ++ ) {
    x = sc . nextInt ( ) ;
    y = sc . nextInt ( ) ;
    temp += y - x ;
    if ( count < temp ) count = temp ;
  }
  out . print ( count ) ;
  out . close ( ) ;
}

public static void main ( String [ ] args ) throws Exception { int n = sc . nextInt ( ) , count = 0 , x = 0 , y = 0 , temp = 0 ; for ( int i = 0 ; i < n ; i ++ ) { x = sc . nextInt ( ) ; y = sc . nextInt ( ) ; temp += y - x ; if ( count < temp ) count = temp ; } out . print ( count ) ; out . close ( ) ; }
(method_declaration (modifiers) type: (void_type) name: (identifier) parameters: (formal_parameters (formal_parameter type: (array_type element: (type_identifier) dimensions: (dimensions)) name: (identifier))) (throws (type_identifier)) body: (block (local_variable_declaration type: (integral_type) declarator: (variable_declarator name: (identifier) value: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list))) 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)) 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 (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)))) (if_statement condition: (parenthesized_expression (binary_expression left: (identifier) right: (identifier))) consequence: (expression_statement (assignment_expression left: (identifier) right: (identifier)))))) (expression_statement (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (identifier)))) (expression_statement (method_invocation object: (identifier) name: (identifier) arguments: (argument_list)))))