Each of the 20 people has 19 other people to communicate to. If you add that all up you get 20*19 paths, but then each path is counted twice (back and forth), so we divide this by 2. 20*19/2 = 190.
The general forumula is n(n-1)/2
They showcase it digitally since their work is done on computers.
Answer:
Following are the code to this question:
please find the attached file.
Explanation:
In this code, four class "novels, magazines, technical journals, and textbooks", is defined, in which it holds their respective default constructor and the get and set method to hold the string and integer value, and in the book class the main method is defined, that creates its object and a switch to for search value and print its value.