"The question in aviation is not how much runway is necessary to take off and land an airplane. The question is how much runway is necessary to make that operation safe." Charles Lindbergh, from his book, "We." 1926
And the answer is given in great detail in CS25 or FAR 25. In this case it would appear there was plenty of room for a safe take off even with a brief reduction in thrust associated with a loud bang and flame.(we call this a surge). There was not however enough room for a safe stop from 2 seconds after "about V1". But to be quite frank there wasn't supposed to be!!!!!
sgg come on down.