first, listen to this song. It's called Daikenkai by a japanese rap group called Des-ROW:
[link]Now, heres the original Soulja Boi song:
[link]Listen to the chorus of both songs. Mind you, Daikenkai was first released in 2001. Meaning, the melody for Crank Dat was stolen, proving Soulja Boi is both a weeaboo and a fan of DDR.