Software Engineer

You are given an integer N. Your task is to return a 2-D ArrayList containing the pascal’s triangle till the row N.

A Pascal's triangle is a triangular array constructed by summing adjacent elements in preceding rows. Pascal's triangle contains the values of the binomial coefficient. For example in the figure below.

For example, given integer N= 4 then you have to print.

1  
1 1 
1 2 1 
1 3 3 1

Here for the third row, you will see that the second element is the summation of the above two-row elements i.e. 2=1+1, and similarly for row three 3 = 1+2 and 3 = 1+2.

You are given an N x M integer matrix. Your task is to modify this matrix in place so that if any cell contains the value 0, then all cells in the same row and column as that cell should also be set to 0.

Requirements:

• If a cell in the matrix has the value 0, set all other cells in that cell's row and column to 0.
• You should perform this modification in place (without using additional matrices).

You must do it in place.

For Example:

If the given grid is this:
[7, 19, 3]
[4, 21, 0]

Then the modified grid will be:
[7, 19, 0]
[0, 0,  0]

Given a binary search tree and an integer ‘K’. Your task is to find the ‘K-th’ smallest element in the given BST( binary search tree).

BST ( binary search tree) -

If all the smallest nodes on the left side and all the greater nodes on the right side of the node current node.

Example -

Order of elements in increasing order in the given BST is - { 2, 3, 4, 5, 6, 7, 8, 10 }

Suppose given ‘K = 3’ then 3rd smallest element is ‘4’.

Suppose given ‘K = 8’ then 8th smallest element is ‘10’.

Note:

1. You are not required to print the output explicitly, it has already been taken care of. Just implement the function and return the ‘K-th’ smallest element of BST.
2. You don’t need to return ‘K-th’ smallest node, return just value of that node. 
3. If ‘K-th’ smallest element is not present in BST then return -1.

You are given an array of n integers (a1, a2,....,an), you need to find if the array contains a pythagorean triplet or not.

An array is said to have a pythagorean triplet if there exists three integers x,y and z in the array such that x^2 + y^2 = z^2.

Note

1. The integers x,y and z might not be distinct , but they should be present at different locations in the array i.e if a[i] = x, a[j] = y and a[k] = z, then i,j and k should be pairwise distinct.
2. The integers a,b and c can be present in any order in the given array.