public static void main ( String [ ] args ) {
  Scanner in = new Scanner ( System . in ) ;
  int R = in . nextInt ( ) ;
  int C = in . nextInt ( ) ;
  char [ ] [ ] A = new char [ R ] [ ] ;
  for ( int r = 0 ;
  r < R ;
  r ++ ) {
    A [ r ] = in . next ( ) . toCharArray ( ) ;
  }
  int minR = Integer . MAX_VALUE ;
  int maxR = Integer . MIN_VALUE ;
  int minC = Integer . MAX_VALUE ;
  int maxC = Integer . MIN_VALUE ;
  int count = 0 ;
  for ( int r = 0 ;
  r < R ;
  r ++ ) {
    for ( int c = 0 ;
    c < C ;
    c ++ ) {
      if ( A [ r ] [ c ] == 'B' ) {
        count ++ ;
        minR = Math . min ( minR , r ) ;
        maxR = Math . max ( maxR , r ) ;
        minC = Math . min ( minC , c ) ;
        maxC = Math . max ( maxC , c ) ;
      }
    }
  }
  int answer ;
  if ( count == 0 ) {
    answer = 1 ;
  }
  else {
    int side = Math . max ( maxR - minR + 1 , maxC - minC + 1 ) ;
    if ( side > R || side > C ) {
      answer = - 1 ;
    }
    else {
      answer = side * side - count ;
    }
  }
  System . out . println ( answer ) ;
}

public static void main ( String [ ] args ) { Scanner in = new Scanner ( System . in ) ; int R = in . nextInt ( ) ; int C = in . nextInt ( ) ; char [ ] [ ] A = new char [ R ] [ ] ; for ( int r = 0 ; r < R ; r ++ ) { A [ r ] = in . next ( ) . toCharArray ( ) ; } int minR = Integer . MAX_VALUE ; int maxR = Integer . MIN_VALUE ; int minC = Integer . MAX_VALUE ; int maxC = Integer . MIN_VALUE ; int count = 0 ; for ( int r = 0 ; r < R ; r ++ ) { for ( int c = 0 ; c < C ; c ++ ) { if ( A [ r ] [ c ] == ' B ' ) { count ++ ; minR = Math . min ( minR , r ) ; maxR = Math . max ( maxR , r ) ; minC = Math . min ( minC , c ) ; maxC = Math . max ( maxC , c ) ; } } } int answer ; if ( count == 0 ) { answer = 1 ; } else { int side = Math . max ( maxR - minR + 1 , maxC - minC + 1 ) ; if ( side > R || side > C ) { answer = - 1 ; } else { answer = side * side - count ; } } System . out . println ( answer ) ; }
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name: (identifier) value: (array_creation_expression type: (integral_type) dimensions: (dimensions_expr (identifier)) dimensions: (dimensions)))) (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: (array_access array: (identifier) index: (identifier)) right: (method_invocation object: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list)) name: (identifier) arguments: (argument_list)))))) (local_variable_declaration type: (integral_type) declarator: (variable_declarator name: (identifier) value: (field_access object: (identifier) field: (identifier)))) (local_variable_declaration type: (integral_type) declarator: (variable_declarator name: (identifier) value: (field_access object: (identifier) field: (identifier)))) (local_variable_declaration type: (integral_type) declarator: (variable_declarator name: (identifier) value: (field_access object: (identifier) field: (identifier)))) (local_variable_declaration type: (integral_type) declarator: (variable_declarator name: (identifier) value: (field_access object: (identifier) field: (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 (for_statement init: (local_variable_declaration type: (integral_type) declarator: (variable_declarator name: (identifier) value: (decimal_integer_literal))) condition: (binary_expression left: 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