swap or reverse
Try to swap or reverse the line as needed.
abcdefghijklmn
abcdefghijklmn bcdefghijklmna cdefghijklmnba defghijklmncba efghijklmndcba fghijklmnedcba ghijklmnfedcba hijklmngfedcba ijklmnhgfedcba jklmnihgfedcba klmnjihgfedcba lmnkjihgfedcba mnlkjihgfedcba nmlkjihgfedcba