static int sumModArr ( int arr [ ] , int n ) {
  int subSum = arr [ n - 1 ] ;
  for ( int i = n - 2 ;
  i >= 0 ;
  i -- ) {
    int curr = arr [ i ] ;
    arr [ i ] -= subSum ;
    subSum += curr ;
  }
  return sumArr ( arr , n ) ;
}

static int sumModArr ( int arr [ ] , int n ) { int subSum = arr [ n - 1 ] ; for ( int i = n - 2 ; i >= 0 ; i -- ) { int curr = arr [ i ] ; arr [ i ] -= subSum ; subSum += curr ; } return sumArr ( arr , n ) ; }
(method_declaration (modifiers) type: (integral_type) name: (identifier) parameters: (formal_parameters (formal_parameter type: (integral_type) name: (identifier) dimensions: (dimensions)) (formal_parameter type: (integral_type) name: (identifier))) body: (block (local_variable_declaration type: (integral_type) declarator: (variable_declarator name: (identifier) value: (array_access array: (identifier) index: (binary_expression left: (identifier) right: (decimal_integer_literal))))) (for_statement init: (local_variable_declaration type: (integral_type) declarator: (variable_declarator name: (identifier) value: (binary_expression left: (identifier) right: (decimal_integer_literal)))) condition: (binary_expression left: (identifier) right: (decimal_integer_literal)) update: (update_expression (identifier)) body: (block (local_variable_declaration type: (integral_type) declarator: (variable_declarator name: (identifier) value: (array_access array: (identifier) index: (identifier)))) (expression_statement (assignment_expression left: (array_access array: (identifier) index: (identifier)) right: (identifier))) (expression_statement (assignment_expression left: (identifier) right: (identifier))))) (return_statement (method_invocation name: (identifier) arguments: (argument_list (identifier) (identifier))))))