Amazon Interview question

test.js

A-B-C-D
|/ /
E-F

A-B C-D
|/ /
E F


//social network


//input userId/userId
//return true/false if that person is in their network

function user(name){
    this.id = randomId
    this.name= name
    this.friends = []
    
    this.addFriend(function(id){
        if(this.friends.includes(id)) return
        this.friends.push(id)
    })
}

var user1= new user('ben')
var user2= new user('Tomasz')

var seen=[]

function areTheyFriends(user1,user2){
    if(user1===null || user2===null || typeof(user1)==='undefined'||typeof(user2)==='undefined') return false
    seen.push(user1)
    if(!user1.friends || !user1.friends.length) return false
    
    
    for(let i=0; i< user1.friends.length <0;i++){
        if(user1.friends[i].id===user2.id) return true
        if(seen.includes(user1.friends[i].id)) continue
        if(areTheyFriends(user1.friends[i].id,user2)){
            return true
        }
    }
    
    return false
}