Repeated Consecutive Digital Product Sum Convergence Given a positive integer n (Example: n=1234444999)


Separate into consecutive digit runs:


[1, 2, 3, 4444, 999]

Take the digital product of each run.


[1, 2, 3, 4*4*4*4, 9*9*9] = [1, 2, 3, 256, 729]

Sum it...


991

Repeat until this converges to a single number:


1234444999
991
82
10
1

Return last number.




Test Cases

BASE CASES:
0 = 0
...
9 = 9

OTHER CASES:
1234444999                     = 1
222222222222222                = 8
111222333444555666777888999000 = 9
11122233344455566677788899     = 8
1112223334445                  = 6
14536                          = 1
99                             = 9


Requested Example:

334455553666333
9+16+625+3+216+27
896
8+9+6
23
2+3
**5**


Winning?

It's code-golf, lowest byte-count is the winner.
05AB1E, 7 6 5 bytes

Thanks to Emigna for saving a byte!

vSγPO


Uses the 05AB1E encoding. Try it online!