public static void main ( String [ ] args ) throws Exception {
  int n = sc . nextInt ( ) , counter = 0 ;
  String input = sc . next ( ) ;
  for ( int i = 0 ;
  i < input . length ( ) - 1 ;
  i ++ ) {
    if ( input . charAt ( i ) == input . charAt ( i + 1 ) ) counter ++ ;
  }
  out . print ( counter ) ;
  out . close ( ) ;
}

public static void main ( String [ ] args ) throws Exception { int n = sc . nextInt ( ) , counter = 0 ; String input = sc . next ( ) ; for ( int i = 0 ; i < input . length ( ) - 1 ; i ++ ) { if ( input . charAt ( i ) == input . charAt ( i + 1 ) ) counter ++ ; } out . print ( counter ) ; 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))) (local_variable_declaration type: (type_identifier) declarator: (variable_declarator name: (identifier) value: (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: (binary_expression left: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list)) right: (decimal_integer_literal))) update: (update_expression (identifier)) body: (block (if_statement condition: (parenthesized_expression (binary_expression left: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (identifier))) right: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (binary_expression left: (identifier) right: (decimal_integer_literal)))))) consequence: (expression_statement (update_expression (identifier)))))) (expression_statement (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (identifier)))) (expression_statement (method_invocation object: (identifier) name: (identifier) arguments: (argument_list)))))