Very recently, I changed my SE username because I made this account some years ago and wanted to get back into asking questions. However, I’m still planning to post questions and potentially earn votes. We can imagine a site that has some issues dealing with name changes. The problem: given a list of names, reputation changes, and name changes, can you create a leaderboard of reputation? **Assume everyone's reputation starts at 0.**

Input comes in any reasonable format, and has two forms: a *name change* `<String, String>` and a *rep change* `<String, Number>`.

What does *any reasonable format* mean? When I write questions, it usually means the input can be rearranged or repackaged to work with the way your language takes in input (do you want a list of pairs? two lists? a string? that’s all fine) as long as it doesn’t add information or otherwise offload some of the computational work onto the human.

Name changes change a person’s username to any username *not currently in use.* For example, if A changes name to D, and B changes name to C, D (previously known as A) could still change their name to A or to B, even though these names have been used before. However, at any given moment the set of names are unique.

Rep changes represent something like getting up/down votes on a post, receiving a bounty, etc. All rep changes are guaranteed to be integers. They might come in the form <“Bob”, 5> or <“Alice”, -53000>. At the end, you must output all usernames that are currently in existence, and their rep counts, in descending order.

Test case:
```
Alice 5
Bob 7
Bob John
John 113
Alice Cheryl
Daniel 13
John Alice
Alice 12
```

Result:
```
Alice 132
Daniel 13
Cheryl 5
```
Test case, suggested by Unrelated String:

```
Jimmy Adam
Donald 12
Amelia -11
```
Result:

```
Donald 12
Adam 0
Amelia -11
```

Test case:
```
CodegoLfer65 12
Bluman 9
CodegoLfer65 n4me
n4me -3
```

Result:
```
Bluman 9
n4me 9 (note: these two can be in either order)
```

Usernames are composed of only [A-Za-z0-9], i.e. alphanumerics. However, the input will not be a number in base 10. This means usernames like `144`, `015` are not allowed.

This question seems heavy on data structures, so golfing languages may not perform as well. Maybe other languages will have a fighting chance? Scoring is by lowest number of bytes, i.e. tag:code-golf .