You are welcome!

Please which language? Read the description again.

r = [r[0] = f(init, a[0]), r[1] = f(r[0], a[1]), r[2] = f(r[1], a[2]), ...]

All the tests are right. Before posting an issue be sure that your program is correct. You could have posted a question instead of an issue:-) Tell me when you succeed.