public static void main ( String [ ] args ) {
  Scanner sc = new Scanner ( System . in ) ;
  int h = sc . nextInt ( ) ;
  int w = sc . nextInt ( ) ;
  int [ ] [ ] grid = new int [ w ] [ h ] ;
  int wCount = 0 ;
  for ( int i = 0 ;
  i < h ;
  i ++ ) {
    String s = sc . next ( ) ;
    for ( int j = 0 ;
    j < w ;
    j ++ ) {
      if ( s . charAt ( j ) == '.' ) {
        grid [ j ] [ i ] = - 1 ;
        wCount ++ ;
      }
      else {
        grid [ j ] [ i ] = Integer . MIN_VALUE ;
      }
    }
  }
  grid [ 0 ] [ 0 ] = 0 ;
  for ( int i = 0 ;
  i < wCount ;
  i ++ ) {
    for ( int j = 0 ;
    j < w ;
    j ++ ) {
      for ( int k = 0 ;
      k < h ;
      k ++ ) {
        if ( grid [ j ] [ k ] == i ) {
          if ( j != 0 ) {
            if ( grid [ j - 1 ] [ k ] == - 1 ) {
              grid [ j - 1 ] [ k ] = i + 1 ;
            }
          }
          if ( j != w - 1 ) {
            if ( grid [ j + 1 ] [ k ] == - 1 ) {
              grid [ j + 1 ] [ k ] = i + 1 ;
            }
          }
          if ( k != 0 ) {
            if ( grid [ j ] [ k - 1 ] == - 1 ) {
              grid [ j ] [ k - 1 ] = i + 1 ;
            }
          }
          if ( k != h - 1 ) {
            if ( grid [ j ] [ k + 1 ] == - 1 ) {
              grid [ j ] [ k + 1 ] = i + 1 ;
            }
          }
        }
      }
    }
    if ( grid [ w - 1 ] [ h - 1 ] != - 1 ) {
      System . out . println ( wCount - grid [ w - 1 ] [ h - 1 ] - 1 ) ;
      return ;
    }
  }
  System . out . println ( - 1 ) ;
}

public static void main ( String [ ] args ) { Scanner sc = new Scanner ( System . in ) ; int h = sc . nextInt ( ) ; int w = sc . nextInt ( ) ; int [ ] [ ] grid = new int [ w ] [ h ] ; int wCount = 0 ; for ( int i = 0 ; i < h ; i ++ ) { String s = sc . next ( ) ; for ( int j = 0 ; j < w ; j ++ ) { if ( s . charAt ( j ) == ' . ' ) { grid [ j ] [ i ] = - 1 ; wCount ++ ; } else { grid [ j ] [ i ] = Integer . MIN_VALUE ; } } } grid [ 0 ] [ 0 ] = 0 ; for ( int i = 0 ; i < wCount ; i ++ ) { for ( int j = 0 ; j < w ; j ++ ) { for ( int k = 0 ; k < h ; k ++ ) { if ( grid [ j ] [ k ] == i ) { if ( j != 0 ) { if ( grid [ j - 1 ] [ k ] == - 1 ) { grid [ j - 1 ] [ k ] = i + 1 ; } } if ( j != w - 1 ) { if ( grid [ j + 1 ] [ k ] == - 1 ) { grid [ j + 1 ] [ k ] = i + 1 ; } } if ( k != 0 ) { if ( grid [ j ] [ k - 1 ] == - 1 ) { grid [ j ] [ k - 1 ] = i + 1 ; } } if ( k != h - 1 ) { if ( grid [ j ] [ k + 1 ] == - 1 ) { grid [ j ] [ k + 1 ] = i + 1 ; } } } } } if ( grid [ w - 1 ] [ h - 1 ] != - 1 ) { System . out . println ( wCount - grid [ w - 1 ] [ h - 1 ] - 1 ) ; return ; } } System . out . println ( - 1 ) ; }
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name: (identifier) value: (array_creation_expression type: (integral_type) dimensions: (dimensions_expr (identifier)) dimensions: (dimensions_expr (identifier))))) (local_variable_declaration type: (integral_type) 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 (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: (identifier)) 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: (character_literal))) consequence: (block (expression_statement (assignment_expression left: (array_access array: (array_access array: (identifier) index: (identifier)) index: (identifier)) right: (unary_expression operand: (decimal_integer_literal)))) (expression_statement (update_expression (identifier)))) alternative: (block (expression_statement (assignment_expression left: (array_access array: (array_access array: (identifier) index: (identifier)) index: (identifier)) right: (field_access object: (identifier) field: (identifier)))))))))) (expression_statement (assignment_expression left: (array_access array: (array_access array: (identifier) index: (decimal_integer_literal)) index: (decimal_integer_literal)) right: (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 (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 (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 (if_statement condition: (parenthesized_expression (binary_expression left: (array_access array: (array_access array: (identifier) index: (identifier)) index: (identifier)) right: (identifier))) consequence: (block (if_statement condition: (parenthesized_expression (binary_expression left: (identifier) right: (decimal_integer_literal))) consequence: (block (if_statement condition: (parenthesized_expression (binary_expression left: (array_access array: (array_access array: (identifier) index: (binary_expression left: (identifier) right: (decimal_integer_literal))) index: (identifier)) right: (unary_expression operand: (decimal_integer_literal)))) consequence: (block (expression_statement (assignment_expression left: (array_access array: (array_access array: (identifier) index: (binary_expression left: (identifier) right: (decimal_integer_literal))) index: (identifier)) right: (binary_expression left: (identifier) right: (decimal_integer_literal)))))))) (if_statement condition: (parenthesized_expression (binary_expression left: (identifier) right: (binary_expression left: (identifier) right: (decimal_integer_literal)))) consequence: (block (if_statement condition: (parenthesized_expression (binary_expression left: (array_access array: (array_access array: (identifier) index: (binary_expression left: (identifier) right: (decimal_integer_literal))) index: (identifier)) right: (unary_expression operand: (decimal_integer_literal)))) consequence: (block (expression_statement (assignment_expression left: (array_access array: (array_access array: (identifier) index: (binary_expression left: (identifier) right: (decimal_integer_literal))) index: (identifier)) right: (binary_expression left: (identifier) right: (decimal_integer_literal)))))))) (if_statement condition: (parenthesized_expression (binary_expression left: (identifier) right: (decimal_integer_literal))) consequence: (block (if_statement condition: (parenthesized_expression (binary_expression left: (array_access array: (array_access array: (identifier) index: (identifier)) index: (binary_expression left: (identifier) right: (decimal_integer_literal))) right: (unary_expression operand: (decimal_integer_literal)))) consequence: (block (expression_statement (assignment_expression left: (array_access array: (array_access array: (identifier) index: (identifier)) index: (binary_expression left: (identifier) right: (decimal_integer_literal))) right: (binary_expression left: (identifier) right: (decimal_integer_literal)))))))) (if_statement condition: (parenthesized_expression (binary_expression left: (identifier) right: (binary_expression left: (identifier) right: (decimal_integer_literal)))) consequence: (block (if_statement condition: (parenthesized_expression (binary_expression left: (array_access array: (array_access array: (identifier) index: (identifier)) index: (binary_expression left: (identifier) right: (decimal_integer_literal))) right: (unary_expression operand: (decimal_integer_literal)))) consequence: (block (expression_statement (assignment_expression left: (array_access array: (array_access array: (identifier) index: (identifier)) index: (binary_expression left: (identifier) right: (decimal_integer_literal))) right: (binary_expression left: (identifier) right: (decimal_integer_literal)))))))))))))) (if_statement condition: (parenthesized_expression (binary_expression left: (array_access array: (array_access array: (identifier) index: (binary_expression left: (identifier) right: (decimal_integer_literal))) index: (binary_expression left: (identifier) right: (decimal_integer_literal))) right: (unary_expression operand: (decimal_integer_literal)))) consequence: (block (expression_statement (method_invocation object: (field_access object: (identifier) field: (identifier)) name: (identifier) arguments: (argument_list (binary_expression left: (binary_expression left: (identifier) right: (array_access array: (array_access array: (identifier) index: (binary_expression left: (identifier) right: (decimal_integer_literal))) index: (binary_expression left: (identifier) right: (decimal_integer_literal)))) right: (decimal_integer_literal))))) (return_statement))))) (expression_statement (method_invocation object: (field_access object: (identifier) field: (identifier)) name: (identifier) arguments: (argument_list (unary_expression operand: (decimal_integer_literal)))))))