Question 1:

A string A is special if A = B + B (an empty string is also special)
example "aa", "aabbaabb" are special, but "aba", "aabb" are not.
Find smallest number of operations to change the given string into a special string

You are given a string 'S' to make it special you can do following operations:

• insert any new charater at any place
• remove any character
• replace any character with any other character

Examples:

"aba" -> 1 // remove 'b' and string becomes "aa"
"a"   -> 1 // either remove or add 'a'

Constraints:
max string length = 100
string characters are [a-z]

Question 2:

A garden is a rectangular grid of squares. Some squares have roses.
We want to assign a gardner who will work on 'k' roses, he will work on a rectangural patch. We want to minimise the cost which is equal to perimeter of the rectangle gardner is working on.

Given two arrays X and Y coordinates of roses and an integer k. Find the min cost.

Constraints:
values of x and y are [0,100] inclusive
X, Y arrays max elements 100

Question 3:

Given a binary representation of a numberr in an array, convert it to base 6 and return the array.

Input : base 2 array
Output : base 6 array

Constraints:
base2 array length can be max 100
how to do this without using int128 or Big Integers?

Can anyone provide me working approaches for these questions!