Statement: a sequence of numbers with 2k elements called "Double" if with k elements from left and k from right, we can create k
pairs that two elements in each pair are equal. Give an array A with n elements, n is even, L numbers at the left and R number at
the right. You can perform these following operations on A any number of times (possibly zero):
replace A_i with x (x <= n)
move 1 element from L to R
move 1 element from R to L
Find the minimum number of operations to make A be a double sequence.
Input: n, L, R and A
6 3 3
1 2 3 2 2 2
Output: minimum number of operations
Please help me!!!