## Editorial for CCC '19 S1 - Flipper

Remember to use this editorial

**only**when stuck, and**not to copy-paste code from it**. Please be respectful to the problem author and editorialist.**Submitting an official solution before solving the problem yourself is a bannable offence.**Author:

Create a 2D array of size .
Let:
`A[0][0] = 1`

,
`A[0][1] = 2`

,
`A[1][0] = 3`

, and
`A[1][1] = 4`

as stated in the problem.

To reflect horizontally, swap `A[0][0]`

with `A[1][0]`

and swap `A[0][1]`

with `A[1][1]`

.

To reflect vertically, swap `A[0][0]`

with `A[0][1]`

and swap `A[1][0]`

with `A[1][1]`

.

For each character in the line of input, perform a horizontal reflection if the character is `H`

and perform a vertical reflection if the character is `V`

.
This solution passes both subtasks.

Then output the 2D array as specified.

**Time complexity:**

## Comments

But the operations are commutative so you can just count the number of flips and mod 2. At most you'll need to do 1 V and 1 H.

Agreed. True time complexity: O(1).