Programmer Analyst

Tip 1 : choose the table wisely
Tip 2 : It is only about the join operation 

I use a for loop to iterate the numbers from 1 to N
Then check for each number to be a prime number. If it is a prime number,stores in a vector
and in the optimisation I told that I would only be traversing the odd numbers
Run a loop from 3 to square root of n.
Then I was going to start with the sieve method but then he moved on with the next question

I take 4 pointers start_row, end_row, Start_col, end_col and intialise with the respective values
start_row=0,end_row=r-1,start_col-0,end_col=c-1
Print the first row using for loop and updated the start_row value by 1
then print the end col using for loop and end_col--
print the end row using for loop and end_row--
print end col using for loop and start_col++

Tip 1 : Know about the company in which you are applying