Surprise Debate

Problem Statement

Surprise Debate Problem Description Angela has N students in her class and has announced a surprise debate. An integer array A has the roll numbers of all N students. For the debate, the students will be grouped into pairs where the student that has smallest roll number will be paired with the student that has the largest roll number, the student that has the second smallest roll number will be paired with the student that has the second largest roll number and so on. A pair can debate if the sum of their roll numbers is divisible by an integer K. In case there is only one student left and twice his/her roll number is divisible by K, that student will debate with Angela. Your task is to find and return an integer value, representing the lowest roll number amongst all the possible divisible pairs. If only one student is left, then return that student's roll number. In case no student is chosen, return -1. Input Specification input1: An integer value N, representing the number of student