[
{
"name": "Acme, Inc.", "close_date": "01-12-2018", "referred_by": "Sprockets"
},
{
"name": "Sprockets", "close_date": "01-09-2018", "referred_by": "Dunder Mifflin"
},
{
"name": "Initech", "close_date": "01-01-2018"
},
{
"name": "Initrode", "close_date": "02-02-2018", "referred_by": "Initech"
},
{
"name": "L&P Construction", "close_date": "01-19-2018", "referred_by": "Initech"
},
{
"name": "Dunder Mifflin", "close_date": "12-01-2017"
}
]The way i took is to use 2 maps. User Map and Monthly Count Map (Per Month Per User)
User Map
| name | referredBy |
|---|---|
| Acme, Inc | Sprocket |
| Initech | null |
| Initrode | Initech |
Monthly Count Map
| date | countMap |
|---|---|
| 01/2018 | Sprocket:1 |
| --- | Initech:1 |
After populating both map, a clean up work is done to set any indirect referral to its root referral.
After the clean up, while printing the result, each countMap for the month will be consolidated using the refined userMap to do lookup, indirect referral is replaced by direct referral.