MIT
25
Proof Outline
lGraph has O(n2) (capacitated) edges
lSo O(n2) work to contract, then two subproblems of size n/2½
»T(n) =  2 T(n/2½) + O(n2) = O(n2 log n)
lAlgorithm fails if both iterations fail
»Iteration succeeds if contractions and recursion succeed
»P(n)=1 - [1 - ½ P(n/2½)]2 = W (1 / log n)