Phone screening

1. question similar to can place flower

boolean canSeatPeople(List seats, int numberOfPlace){
}

2. Given the standard mapping from English letters to digits on a phone keypad (1 → "" 2 -> a,b,c 3 -> d,e,f 4 -> g,h,i 5 -> j,k,l 6 -> m,n,o 7 -> p,q,r,s 8 -> t,u,v 9 -> w,x,y,z),
   write a program that outputs all words that can be formed from any n-digit phone number from the list of given KNOWN_WORDS considering the mapping mentioned above.
   KNOWN_WORDS= ['careers', 'linkedin', 'hiring', 'interview', 'linkedgo']
   phoneNumber: 2273377
   Output: ['careers']
   phoneNumber: 54653346
   Output: ['linkedin', 'linkedgo']

Follow up: Add functions for adding and removing words from known words.