Software Engineer

You are given an integer 'N'. For a given 'N' x 'N' chessboard, find a way to place 'N' queens such that no queen can attack any other queen on the chessboard.

A queen can be killed when it lies in the same row, or same column, or the same diagonal of any of the other queens. You have to print all such configurations.

Ninja has a number ‘N’. He wants to print the pattern in such a way that the outer rectangle is of the number ‘N’ and the number goes on decreasing as we move inside the rectangles.

For example, if ‘N’ = 4, then pattern will be:

4 4 4 4 4 4 4 
4 3 3 3 3 3 4 
4 3 2 2 2 3 4 
4 3 2 1 2 3 4 
4 3 2 2 2 3 4 
4 3 3 3 3 3 4 
4 4 4 4 4 4 4 

You have been given an integer array/list(arr) and a number 'Sum'. Find and return the total number of pairs in the array/list which when added, results equal to the 'Sum'.

Note:

Given array/list can contain duplicate elements.

(arr[i],arr[j]) and (arr[j],arr[i]) are considered same.

Ninja is given a binary number as a string ‘S’ of size ‘N’, he is asked to convert it into its decimal equivalent (as an Integer) and print it.

Note:

A binary string is a string in which all characters are either ‘1’ or ‘0’.