public static void main ( String [ ] args ) {
  Scanner sc = new Scanner ( System . in ) ;
  int a = sc . nextInt ( ) ;
  int b = sc . nextInt ( ) ;
  if ( a > b ) {
    a = a ^ b ;
    b = a ^ b ;
    a = a ^ b ;
  }
  int rem = b - a ;
  int n = rem / 2 ;
  int x = n * ( n + 1 ) ;
  if ( rem % 2 == 1 ) x += ( n + 1 ) ;
  System . out . println ( x ) ;
}

public static void main ( String [ ] args ) { Scanner sc = new Scanner ( System . in ) ; int a = sc . nextInt ( ) ; int b = sc . nextInt ( ) ; if ( a > b ) { a = a ^ b ; b = a ^ b ; a = a ^ b ; } int rem = b - a ; int n = rem / 2 ; int x = n * ( n + 1 ) ; if ( rem % 2 == 1 ) x += ( n + 1 ) ; System . out . println ( x ) ; }
(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)))) (if_statement condition: (parenthesized_expression (binary_expression left: (identifier) right: (identifier))) consequence: (block (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)))))) (local_variable_declaration type: (integral_type) declarator: (variable_declarator name: (identifier) value: (binary_expression left: (identifier) right: (identifier)))) (local_variable_declaration type: (integral_type) declarator: (variable_declarator name: (identifier) value: (binary_expression left: (identifier) right: (decimal_integer_literal)))) (local_variable_declaration type: (integral_type) declarator: (variable_declarator name: (identifier) value: (binary_expression left: (identifier) right: (parenthesized_expression (binary_expression left: (identifier) right: (decimal_integer_literal)))))) (if_statement condition: (parenthesized_expression (binary_expression left: (binary_expression left: (identifier) right: (decimal_integer_literal)) right: (decimal_integer_literal))) consequence: (expression_statement (assignment_expression left: (identifier) right: (parenthesized_expression (binary_expression left: (identifier) right: (decimal_integer_literal)))))) (expression_statement (method_invocation object: (field_access object: (identifier) field: (identifier)) name: (identifier) arguments: (argument_list (identifier))))))