Algorithm 2. (modified G-PPA)
Step 1. Let η ≥ 1 , x 0 ∈ X , ζ > 0 and put k : = 0 .
Step 2. If 0 ∈ T ( ζ k , x k ) , then stop; otherwise, go to Step 3.
Step 3. Put { ζ k } ⊆ ( 0, ζ ) and if 0 ∉ T ( ζ k , x k ) , choose t k such that t k ∈ T ( ζ k , x k ) and ‖ t k ‖ ≤ η dist ( 0 , T ( ζ k , x k ) ) .
Step 4. Write x k + 1 : = x k + t k .
Step 5. Set k by k + 1 and go to Step 2.