Challenge: Super Washing Machine

Question

You have n super washing machines on a line. Initially, each washing machine has some dresses or is empty.

For each move, you could choose any m (1 ≤ m ≤ n) washing machines, and pass one dress of each washing machine to one of its adjacent washing machines at the same time .

Given an integer array representing the number of dresses in each washing machine from left to right on the line, you should find the minimum number of moves to make all the washing machines have the same number of dresses.

Answer 1

If it is not possible to do it, return -1.

Example1

Input: [1,0,5]
Output: 3
Explanation:
1st move: 1 0 <-- 5 => 1 1 4
2nd move: 1 <-- 1 <-- 4 => 2 1 3
3rd move: 2 1 <-- 3 => 2 2 2

Example2

Input: [0,3,0]
Output: 2
Explanation:
1st move: 0 <-- 3 0 => 1 2 0
2nd move: 1 2 --> 0 => 1 1 1

Example3

Input: [0,2,0]
Output: -1
Explanation: It's impossible to make all the three washing machines have the same number of dresses.

Note:

The range of n is [1, 10000].The range of dresses number in a super washing machine is [0, 1e5].

Answer 2

For the sake of the algorithm - can we move a dress from a machine to *any* other machine, skipping the adjacency, provided that we increase the move counter by the difference between the two machines' positions?

Answer 3

That's what I meant, actually. So if I increase the counter by 3 not 1, it's okay?

Answer 4

Yeah, okay

Answer 5

No you can't move to any washing machine. If you moved to 3rd washing machine, the total move will be 3 instead 1 as you can't go directly there

Answer 6

My response in Ruby:

https://code.sololearn.com/cO80d3k72b0P/?ref=app

Quick and still needs a bit of polish, but runnable. Allows only movements of single dresses between adjacent machines. Takes user input number to represent dresses in machines (each digit representing those dresses in a single washing machine).

Answer 7

my practice on python https://code.sololearn.com/c3YMVt5Lz8R1/#py

Answer 8

I reworked and fixed up my code, now it better handles the trickier cases I've thrown at it. Should show the optimal minimum dress switches!

https://code.sololearn.com/cO80d3k72b0P/?ref=app

(Again, takes user input to represent dresses in machines, with each digit representing the number of dresses in a single machine.)