public static void main ( String [ ] $ ) {
  Scanner s = new Scanner ( System . in ) ;
  int r = s . nextInt ( ) , c = s . nextInt ( ) , k = s . nextInt ( ) ;
  int [ ] cx = new int [ r ] , cy = new int [ c ] , ccx = new int [ k + 1 ] , ccy = new int [ k + 1 ] ;
  Map < Integer , List < Integer >> p = new HashMap < > ( ) ;
  for ( int n = s . nextInt ( ) ;
  n > 0 ;
  -- n ) {
    int X = s . nextInt ( ) - 1 , Y = s . nextInt ( ) - 1 ;
    p . computeIfAbsent ( X , ( i ) -> new ArrayList < > ( ) ) . add ( Y ) ;
    cx [ X ] ++ ;
    cy [ Y ] ++ ;
  }
  for ( int X : cx ) if ( X < k + 1 ) ccx [ X ] ++ ;
  for ( int Y : cy ) if ( Y < k + 1 ) ccy [ Y ] ++ ;
  long res = 0 ;
  for ( int x = 0 ;
  x < r ;
  ++ x ) {
    int need = k - cx [ x ] ;
    if ( need < 0 ) continue ;
    int CY = ccy [ need ] ;
    if ( p . containsKey ( x ) ) {
      for ( int y : p . get ( x ) ) {
        if ( cy [ y ] - 1 == need ) ++ res ;
        if ( cy [ y ] == need ) -- CY ;
      }
    }
    res += CY ;
  }
  System . out . println ( res ) ;
}

public static void main ( String [ ] $ ) { Scanner s = new Scanner ( System . in ) ; int r = s . nextInt ( ) , c = s . nextInt ( ) , k = s . nextInt ( ) ; int [ ] cx = new int [ r ] , cy = new int [ c ] , ccx = new int [ k + 1 ] , ccy = new int [ k + 1 ] ; Map < Integer , List < Integer > > p = new HashMap < > ( ) ; for ( int n = s . nextInt ( ) ; n > 0 ; -- n ) { int X = s . nextInt ( ) - 1 , Y = s . nextInt ( ) - 1 ; p . computeIfAbsent ( X , ( i ) -> new ArrayList < > ( ) ) . add ( Y ) ; cx [ X ] ++ ; cy [ Y ] ++ ; } for ( int X : cx ) if ( X < k + 1 ) ccx [ X ] ++ ; for ( int Y : cy ) if ( Y < k + 1 ) ccy [ Y ] ++ ; long res = 0 ; for ( int x = 0 ; x < r ; ++ x ) { int need = k - cx [ x ] ; if ( need < 0 ) continue ; int CY = ccy [ need ] ; if ( p . containsKey ( x ) ) { for ( int y : p . get ( x ) ) { if ( cy [ y ] - 1 == need ) ++ res ; if ( cy [ y ] == need ) -- CY ; } } res += CY ; } System . out . println ( res ) ; }
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