SDE - 1

You have been given an array/list 'ARR' consisting of 'N' integers. Your task is to find the majority element in the array. If there is no majority element present, print -1.

Note:

A majority element is an element that occurs more than floor('N' / 2) times in the array.

You have been given a matrix ‘MAT’ of size 'N' * 'M' (where 'N' and 'M' denote the number of rows and columns respectively) and a positive integer ‘K’. Your task is to rotate the matrix to the right 'K' times.

Note:

Right rotation on a matrix is shifting each column to the right side (the last column moves to the first column) and 'K' times means performing this rotation 'K' times.

Example:

For 'K' = 1 and the given 'MAT':

1 2 3
4 5 6
7 8 9

Output after rotating 'MAT' one time is:

3 1 2 
6 4 5
9 7 8

An expression is called the postfix expression if the operator appears in the expression after the operands.

Example :

Infix expression: A + B  *  C - D 

Postfix expression:  A B + C D - *

Given a postfix expression, the task is to evaluate the expression. The answer could be very large, output your answer modulo (10^9+7). Also, use modular division when required.

Note:

1. Operators will only include the basic arithmetic operators like '*', '/', '+', and '-'.

2. The operand can contain multiple digits. 

3. The operators and operands will have space as a separator between them.

4. There won’t be any brackets in the postfix expression.