What is big and Little Endian ?

Little and big endian are two ways of storing multibyte data-types ( int, float, etc). In little endian machines, last byte of binary representation of the multibyte data-type is stored first. On the other hand, in big endian machines, first byte of binary representation of the multibyte data-type is stored first.

Big Endian(Wikipedia)

Little Endian(Wikipedia)

Is there a quick way to determine endianness of your machine?
There are n no. of ways for determining endianness of your machine. Here is one quick way of doing the same.

In the above program, a character pointer c is pointing to an integer i. Since size of character is 1 byte when the character pointer is de-referenced it will contain only first byte of integer. If machine is little endian then *c will be 1 (because last byte is stored first) and if machine is big endian then *c will be 0.

Hey i am writing post after a long time.

I was working in git and committed some changes, i forgot to pushed to branch and i forgot the commit too. I reseted the HEAD :(.

So, you just did a git reset --hard HEAD^ and threw out your last commit. Well, it turns out you really did need those changes. . Don’t fear, git should still have your commit. When you do a reset, the commit you threw out goes to a “dangling” state. It’s still in git’s datastore, waiting for the next garbage collection to clean it up. So unless you’ve ran a git gc since you tossed it, you should be in the clear to restore it.

$ git show-ref -h HEAD
  7c61179cbe51c050c5520b4399f7b14eec943754 HEAD

$ git reset --hard HEAD^
  HEAD is now at 39ba87b Fixing about and submit pages so they don't look stupid

$ git show-ref -h HEAD
  39ba87bf28b5bb223feffafb59638f6f46908cac HEAD

So our HEAD has been backed up by one commit. At this point if we wanted it back we could just git pull, but we’re assuming that only our local repository knows about the commit. We need the SHA1 of the commit so we can bring it back. We can prove that git knows about the commit still with the fsck command:

$ git fsck --lost-found
  [... some blobs omitted ...]
  dangling commit 7c61179cbe51c050c5520b4399f7b14eec943754

You can also see the that git knows about the commit still by using the reflogcommand:

$ git reflog
  39ba87b... HEAD@{0}: HEAD~1: updating HEAD
  7c61179... HEAD@{1}: pull origin master: Fast forward
  [... lots of other refs ...]

So, we now have our SHA1: 7c61179. If we want to get immediately apply it back onto our current branch, doing a git merge will recover the commit:

$ git merge 7c61179
  Updating 39ba87b..7c61179
  Fast forward
    css/screen.css |    4 ++++
    submit.html    |    4 ++--
    2 files changed, 6 insertions(+), 2 deletions(-)

This command will bring your lost changes back and make sure that HEAD is pointing at the commit. From here you can continue to work as normal! You could also checkout the SHA1 into a new branch, but really a merge is the fastest and easiest way to restore that lost commit once you have the hash. If you have other ways let us know in the comments!

Thanx to gitReady for this valuable post.

Imagine you sell those metallic digits used to number houses, locker doors, hotel rooms, etc. You need to find how many of each digit to ship when your customer needs to number doors/houses:
1 to 100
51 to 300
1 to 2,000 with zeros to the left
The obvious solution is to do a loop from the first to the last number, convert the counter to a string with or without zeros to the left, extract each digit and use it as an index to increment an array of 10 integers.
I wonder if there is a better way to solve this, without having to loop through the entire integers range.
GitHub Link
Thanx to mathematician’s Post that helped me to understand the complexity of problem, i just understood the equation and converted it to code. Enjoy !