|
|
|
|
|
|
by HarHarVeryFunny
165 days ago
|
|
|
Isn't he also using 2N operations? To swap B and D, with intervening C (i.e. B C D), what he his doing is individually reversing each of B C, and D (= total N swaps), then reversing the combined B' C' D' (= another N swaps). |
|
|