Minimum no of swaps to be done in an array such that, no two adjacent elements are same.

Question

1.00/5 (1 vote)

See more:

Minimum no of swaps to be done in an array such that, no two adjacent elements are same.

n = 6 a[] = {1, 1, 5, 2, 5, 5} answer = 1 ( swap a[0] with a[4] or a[5] )

n = 8 a[] = {1, 5, 5, 1, 4, 6, 1, 1} answer = 2 (swap a[0] with a[1] and a[5] with a[6] )
n = 8 a[] = {3, 1, 1, 5, 3, 3, 5, 5} answer = 2 (swap a[0] with a[1] and a[5] with a[6] )
indexing from zero in above examples.

Refer for question: Minimum no of swaps to be done in an array such that, no two adjacent elements are same. - Codeforces[^]

What I have tried:

Logic 1: count total number of consecutive pairs, and subtract it from the count of remainder elements. But it doesnt seem to work in all cases.

Posted 6-Feb-18 6:54am

Member 13664362

Updated 6-Feb-18 9:40am

CHill60

Add a Solution

1 solution

Add a Solution

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

Patrice T · Answer 1 · 2018-02-06T09:40:00

This is a contest, so by definition, you have to find a solution yourself.
So if we give you a solution, it will mean that you failed.

Quote:
Logic 1: count total number of consecutive pairs, and subtract it from the count of remainder elements. But it doesnt seem to work in all cases.

That mean that you have to refine your algorithm.
Find samples that don't work and search what changes to do to your algorithm.
Note that some samples can have no solution:

n = 4 a[] = {1, 1, 2, 1} answer = 0, no solution
n = 5 a[] = {1, 1, 2, 1, 2} answer = 2  (swap a[1] with a[2] and a[3] with a[4] )

[Update]

Quote:
Im not able to solve the question, and there is not much help online.

Try to device a brut force algorithm: try every possible swap and combinations of multiples swaps.