Exodia
Principle of Computer Operation

The answer is c. 36======analyzing the for-loop, we see that the control variable, k, starts at 0 and increments by after every loop iteration. the condition  tells us that the loop will stop when k is above 7; in this case, when k is 8.0 1 2 3 4 5 6 7 are the values for k that will be used. each number is for each iteration; therefore, the for-loop will have 8 iterations in total.the code inside the loop itself goes like this: 1st iteration (k=0)starting with sum=0, val=1    means that add  to  .since sum is 0 and val is 1, 0 + 1 = 1. the new value of sum is 1.    means to increment  by 1.since val is 1, the new value of val of 2.end of iteration with  k=0; k is increased by one to become  k=12nd iteration (k=1)starting with sum=1, val=2    ======let us establish a pattern. this is moreso logic than programming: we can  rewrite so that we have the elements from the previous iteration. the 1 came from 0 + 1 before. so we can write it as      .and if we did the third iteration, by the end, sum would look like      notice how the number of plus signs is equal to the iteration you are on (which is just k+1), and what is being added is increasing by one each time.  for example, the third iteration (k=2)  ends up with  with 3 plus signs.the second iteration (k=1) ends up with  with two plus signs.the first iteration (k=0) ends up with  with one plus sign.this is a pattern. the nth iteration will have n plus signs.since we established before that there are 8 iterations of this loop in total, the value of sum at k=7 (the 8th and last iteration) will have sum with 8 plus signs.    so the value of sum at the end of the loop is 36.

You should always remember that sql is pretty useless to learn about since most sites aren't vulnrable to sql anymore. thedatabase management of an sql database is done with php the actual database is a sql database, but websites interact with databases using php. php coukd mean the site is vulnerable to sqli, but that is only an issue if proper measures aren't put into place, it can be. you don't need php in the url for it to be php it's the code that runs the actual site,it manages databases, actions etc. php runs the whole backend of a site. you could try to put an apostrophe in the url or password input to see if there is an error. if the domain name isnt vulnerable to sqli, that means every file path of the domain probably isn't vulnerable because they are aware of sqli. you should also see what fourm script the site is running. for example, if they are running mybb, there could be a vuln in mybb itself or one of the plugins it uses. another thing you should be able to do is identify if a site even uses sql. for example, a site like roblox may use sql because it has accounts and inorder to have accounts php is used. another way would be to look and see if the site has for example id=1 add a ' after it. if the site is vulnerable you'll see a sql error. but no one cares about sqli it is pretty much dead so telling you this is pointless.

Don't forget to put the right neasures into place otherwise your program will be vulnrable to sql injections.