Two cases if we see a ' * ' a ) We ignore ' * ' ' ▁ character ▁ and ▁ move ▁ to ▁ next ▁ character ▁ in ▁ the ▁ pattern , ▁ i . e . , ▁ ' * ' ▁ indicates ▁ an ▁ empty ▁ sequence . ▁ b ) ▁ ' * ' character matches with ith  character in input
if ( pattern . charAt ( j - 1 ) == ' * ' ) lookup [ i ] [ j ] = lookup [ i ] [ j - 1 ] || lookup [ i - 1 ] [ j ] ;