Is time complexity more important than space complexity?

I’ve noticed quite a few cryptographic algorithms speak mainly of the time complexity of an algorithm. For example, with a hashing function h, find x given y = h(x). We normally speak on how long it will take. Or the time to find the discrete log for a public key.


While writing this question, I pondered that maybe because for most algorithms in cryptography (that I have seen) , have O(1) space time complexity. i.e. If the solution does not work, we throw it away and encrypt.

Clarification on this will be really helpful.

Why is it important for functions to be anonymous in lambda calculus?

I was watching the lecture by Jim Weirich, titled ‘Adventures in Functional Programming’. In this lecture, he introduces the concept of Y-combinators, which essentially finds the fixed point for higher order functions.

One of the motivations, as he mentions it, is to be able to express recursive functions using lambda calculus so that the theory by Church (anything that is effectively computable can be computed using lambda calculus) stays.

The problem is that a function cannot call itself simply so, because lambda calculus does not allow named functions, i.e.,

$ $ n(x, y) = x + y$ $

cannot bear the name ‘$ n$ ‘, it must be defined anonymously:

$ $ (x, y) \rightarrow x + y $ $

Why is it important for lambda calculus to have functions that are not named? What principle is violated if there are named functions? Or is it that I just misunderstood jim’s video?

Accidently removed very important file of my project by comman “cp”. Really need help

Very Long story short. In essence this is the problem.

I had some of my project files ( which I was working on for quite sometime. I created one backup of these files two months ago(, and basically what I did was “> cp”. And I have lost all the changes made in last two months.

Is there any way to recover these files. Any help is appritiated.

How important is sprint test plan in agile?

I have been preparing a test plan for every sprint even if I have a master test plan just to plan the test for the current sprint. I am including topics like:

  1. Introduction
  2. Purpose
  3. Feature Overview
  4. Inscope
  5. Outscope
  6. Assumptions and Risks
  7. Approach
  8. Test Deliverables
  9. Testing Task and Proposed Schedule

Recently after discussing with some of my fellow mates and colleagues. They suggested not to make a sprint test plan and is covered by the master test plan. Is it ok to not make a Sprint Test Plan and go on with the master test plan?