Groups linked by follows

There are n users on a social network, numbered from 0 to n - 1. A record [a, b] in follows means that a follows b.

No matter who follows whom, two people are linked if there is a follow record between them. People who can reach one another by going along these links all belong to one group, and a person with no follow records at all forms a group on their own.

Complete the function solution, which returns the number of groups.

Function

solution(n, follows)

Constraints

• n is an integer from 1 to 900.
• The length of follows is from 0 to 10,000.
• Each element of follows has the form [a, b], where a and b are different integers from 0 to n - 1.
• The same record never appears twice. [a, b] and [b, a] are different records.

Examples

Starter code

def solution(n, follows):
    answer = 0
    return answer