static int anagram_pairs ( String [ ] s , int n ) {
  Map < String , Integer > mp = new HashMap < > ( ) ;
  for ( int i = 0 ;
  i < n ;
  i ++ ) {
    char [ ] chArr = s [ i ] . toCharArray ( ) ;
    Arrays . sort ( chArr ) ;
    s [ i ] = new String ( chArr ) ;
    if ( mp . containsKey ( s [ i ] ) ) {
      mp . put ( s [ i ] , mp . get ( s [ i ] ) + 1 ) ;
    }
    else {
      mp . put ( s [ i ] , 1 ) ;
    }
  }
  int ans = 0 ;
  for ( Map . Entry < String , Integer > i : mp . entrySet ( ) ) {
    int k = i . getValue ( ) ;
    ans += ( k * ( k - 1 ) ) / 2 ;
  }
  return ans ;
}

static int anagram_pairs ( String [ ] s , int n ) { Map < String , Integer > mp = new HashMap < > ( ) ; for ( int i = 0 ; i < n ; i ++ ) { char [ ] chArr = s [ i ] . toCharArray ( ) ; Arrays . sort ( chArr ) ; s [ i ] = new String ( chArr ) ; if ( mp . containsKey ( s [ i ] ) ) { mp . put ( s [ i ] , mp . get ( s [ i ] ) + 1 ) ; } else { mp . put ( s [ i ] , 1 ) ; } } int ans = 0 ; for ( Map . Entry < String , Integer > i : mp . entrySet ( ) ) { int k = i . getValue ( ) ; ans += ( k * ( k - 1 ) ) / 2 ; } return ans ; }
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