**Click here to download the complete ISC 2020 Computer Science Paper 2 (Practical).**

**Question:**

A **Prime-Adam** integer is a positive integer (without leading zeros) which is a prirne as well as an Adam number.

Prime number : A number which has only two factors, i.e. 1 and the number itself.

Example: 2, 3, 5, 7 …etc.

Adam number: The square of a number and the square of its reverse are reverse to each other.

Exarnple: If n=13 and reverse of ‘n’ =31, then,

(13)^{2 } = 169

(31)^{2 } = 961 which is reverse of 169

thus 13, is an Adam number.

Accept two positive integers m and n, where m is less than n as user input. Display all Prime-Adam integers that are in the range between m and n (both inclusive) and output them along with the frequency, in the format given below:

Test your program with the following data and some random data:

**Example 1 **

**INPUT: **

m=5

n=100

**OUTPUT:**

THE PRIME-ADAM INTEGERS ARE:

11 13 31

FREQUENCY OF PRIME-ADAM INTEGERS IS: 3

**Example 2**

**INPUT: **

m=100

n=200

**OUTPUT: **

THE PRIME-ADAM INTEGERS ARE:

101 103 113

FREQUENCY OF PRIME-ADAM INTEGERS IS: 3

**Example 3**

**INPUT:**

m=50

n=70

**OUTPUT:**

THE PRIME-ADAM INTEGERS ARE:

NIL

FREQUENCY OF PRIME-ADAM INTEGERS IS: 0

**Example 4**

**INPUT: **m=700

n=450

**OUTPUT: **INVALID INPUT.

**Programming Code:**

/** * The class ISC2020_Q1 inputs a lower and an upper range * and prints all the Prime-Adam numbers within that range * @author : www.guideforschool.com * @Program Type : BlueJ Program - Java * @Question Year : ISC Practical 2020 Question 1 */ import java.util.*; class ISC2020_Q1 //the main class { boolean isPrime(int n) //to check for prime number { int c = 0; for(int i=1; i<=n; i++) { if(n%i == 0) { c++; } } if(c == 2) return true; else return false; } int reverseNum(int n) //to reverse a number { int r = 0, d = 0; while(n > 0) { d = n%10; r = r*10 + d; n = n/10; } return r; } boolean isAdam(int n) //to check for Adam number { int rev = reverseNum(n); int sqn = n*n; int sqr = rev * rev; //square of reverse int rsqn = reverseNum(sqn); //reverse of square if(rsqn == sqr) return true; else return false; } public static void main(String args[]) //the main method { Scanner sc = new Scanner(System.in); System.out.print("Enter the lower limit : "); int m = sc.nextInt(); System.out.print("Enter the upper limit : "); int n = sc.nextInt(); ISC2020_Q1 ob = new ISC2020_Q1(); if(m<1 || n<1 || m>n) //checking for invalid input { System.out.println("INVALID INPUT"); } else { int c = 0; System.out.println("THE PRIME-ADAM INTEGERS ARE:"); for(int i=m; i<=n; i++) { if(ob.isPrime(i) && ob.isAdam(i)) //checking for prime-adam number { c++; System.out.print(i + "\t"); } } if(c == 0) System.out.print("NIL"); System.out.println("\nFREQUENCY OF PRIME-ADAM INTEGERS IS:" + c); } } }

**Output:**

Enter the lower limit : 100

Enter the upper limit : 200

THE PRIME-ADAM INTEGERS ARE:

101 103 113

FREQUENCY OF PRIME-ADAM INTEGERS IS:3