(0) Obligation:

Runtime Complexity TRS:
The TRS R consists of the following rules:

cf(n__g(n__c))
f(n__g(X)) → g(activate(X))
g(X) → n__g(X)
cn__c
activate(n__g(X)) → g(X)
activate(n__c) → c
activate(X) → X

Rewrite Strategy: FULL

(1) InfiniteLowerBoundProof (EQUIVALENT transformation)

The loop following loop proves infinite runtime complexity:
The rewrite sequence
c →+ g(c)
gives rise to a decreasing loop by considering the right hand sides subterm at position [0].
The pumping substitution is [ ].
The result substitution is [ ].

(2) BOUNDS(INF, INF)