Analysis

Let c_i = O(c) be the number of cascading cuts

= (t(H) + c) + 2(m(H) - c + 2), c-1 unmarked, 1 marked

= O(c) + (t(H) + c) + 2(m(H) - c + 2) - (t(H) + 2m(H))

= O(c) + 4 - c

= O(1)