Driver program
let mat = [ [ ' ' , ' ' , ' ' ] , [ ' ' , ' ' , ' ' ] , [ ' ' , ' ' , ' ' ] ] ; document . write ( getLen ( mat , ' ' ) + " " ) ; document . write ( getLen ( mat , ' ' ) + " " ) ; document . write ( getLen ( mat , ' ' ) + " " ) ; document . write ( getLen ( mat , ' ' ) ) ;