ISC Computer Science - Competency Focused Practice Questions (CISCE, August 2024) with Answers

String str = "15.45";
double d = (double) (Double.parseDouble(str));

import java.util.Scanner;

class Automorphic
{
    int l, u;      // lower and upper limits of the range
    int count;     // frequency of automorphic numbers in the range

    // parameterised constructor
    Automorphic(int l, int u)
    {
        this.l = l;
        this.u = u;
        count = 0;
    }

    // returns true if n is an automorphic number
    boolean check(int n)
    {
        long sq = (long) n * n;
        String ns = Integer.toString(n);
        String sqs = Long.toString(sq);
        return sqs.endsWith(ns);
    }

    // checks every number in the range, displays the automorphic ones and their frequency
    void list()
    {
        System.out.println("List of Automorphic numbers from " + l + " to " + u + " :");
        System.out.println("Number\tSquare");
        count = 0;
        for (int i = l; i <= u; i++)
        {
            if (check(i))
            {
                long sq = (long) i * i;
                System.out.println(i + "\t" + sq);
                count++;
            }
        }
        System.out.println("Frequency of Automorphic numbers between " + l + " to " + u + " : " + count);
    }

    public static void main(String[] args)
    {
        Scanner sc = new Scanner(System.in);
        System.out.print("Enter the lower limit of the range->");
        int l = sc.nextInt();
        System.out.print("Enter the upper limit of the range->");
        int u = sc.nextInt();
        Automorphic ob = new Automorphic(l, u);
        ob.list();
    }
}

import java.util.Scanner;

class Anagram
{
    String s1, s2;   // the two words in lower case
    int l1, l2;      // number of characters in s1 and s2

    // parameterised constructor
    Anagram(String s1, String s2)
    {
        this.s1 = s1;
        this.s2 = s2;
        l1 = s1.length();
        l2 = s2.length();
    }

    // sorts the characters of c[] in ascending order using bubble sort
    void sort(char c[])
    {
        int n = c.length;
        for (int i = 0; i < n - 1; i++)
            for (int j = 0; j < n - 1 - i; j++)
                if (c[j] > c[j + 1])
                {
                    char t = c[j];
                    c[j] = c[j + 1];
                    c[j + 1] = t;
                }
    }

    // checks if str1 and str2 are anagrams by sorting both and comparing
    boolean areAnagram(char[] str1, char[] str2)
    {
        if (str1.length != str2.length)
            return false;
        sort(str1);
        sort(str2);
        for (int i = 0; i < str1.length; i++)
            if (str1[i] != str2[i])
                return false;
        return true;
    }

    // converts s1 and s2 to character arrays and displays the result
    void check()
    {
        char c1[] = s1.toCharArray();
        char c2[] = s2.toCharArray();
        if (areAnagram(c1, c2))
            System.out.println(s1 + " and " + s2 + " are anagram of each other");
        else
            System.out.println(s1 + " and " + s2 + " are not anagram of each other");
    }

    public static void main(String[] args)
    {
        Scanner sc = new Scanner(System.in);
        System.out.print("Enter first word->");
        String s1 = sc.next();
        System.out.print("Enter second word->");
        String s2 = sc.next();
        Anagram ob = new Anagram(s1, s2);
        ob.check();
    }
}

class Spy
{
    int num;   // stores the number

    // constructor (assumed already defined)
    Spy(int nn)
    {
        num = nn;
    }

    // recursively returns the sum of the digits of i
    int sumOfDigits(int i)
    {
        if (i == 0)
            return 0;
        else
            return i % 10 + sumOfDigits(i / 10);
    }

    // recursively returns the product of the digits of i
    int prodOfDigits(int i)
    {
        if (i == 0)
            return 1;
        else
            return (i % 10) * prodOfDigits(i / 10);
    }

    // checks whether num is a Spy number and displays the result
    void check()
    {
        int s = sumOfDigits(num);
        int p = prodOfDigits(num);
        if (s == p)
            System.out.println(num + " is a Spy number.");
        else
            System.out.println(num + " is not a Spy number.");
    }

    public static void main(String args[])
    {
        Spy ob = new Spy(1124);
        ob.check();
    }
}

import java.util.Scanner;

class Sports
{
    double height[];   // height of each player
    String name;       // name of the team
    int n;              // total number of players

    // default constructor
    Sports() {}

    // parameterised constructor
    Sports(int n, String name)
    {
        this.n = n;
        this.name = name;
        height = new double[n];
    }

    // accepts the height of every player
    void fillHeight()
    {
        Scanner sc = new Scanner(System.in);
        for (int i = 0; i < n; i++)
        {
            System.out.print("Enter height of player " + (i + 1) + ": ");
            height[i] = sc.nextDouble();
        }
    }

    // returns the average height of the team
    double averageHeight()
    {
        double sum = 0;
        for (int i = 0; i < n; i++)
            sum += height[i];
        return sum / n;
    }

    // compares the average heights of s1 and s2, returns the winning team's name
    // or the equal-height message
    String compare(Sports s1, Sports s2)
    {
        double a1 = s1.averageHeight();
        double a2 = s2.averageHeight();
        if (a1 > a2)
            return s1.name;
        else if (a2 > a1)
            return s2.name;
        else
            return "Both teams have the same average height.";
    }

    // displays the message stored in msg
    void display(String msg)
    {
        System.out.println(msg);
    }

    public static void main(String args[])
    {
        Scanner sc = new Scanner(System.in);
        System.out.print("Enter number of players in team 1: ");
        int n1 = sc.nextInt();
        sc.nextLine();
        System.out.print("Enter name of team 1: ");
        String name1 = sc.nextLine();
        Sports t1 = new Sports(n1, name1);
        t1.fillHeight();

        System.out.print("Enter number of players in team 2: ");
        int n2 = sc.nextInt();
        sc.nextLine();
        System.out.print("Enter name of team 2: ");
        String name2 = sc.nextLine();
        Sports t2 = new Sports(n2, name2);
        t2.fillHeight();

        Sports t3 = new Sports();
        String result = t3.compare(t1, t2);
        t3.display(result);
    }
}

import java.util.Scanner;

class Mix_sort
{
    int a[][];   // stores the integer array
    int m;       // number of rows
    int n;       // number of columns

    // parameterised constructor
    Mix_sort(int row, int col)
    {
        m = row;
        n = col;
        a = new int[m][n];
    }

    // accepts the integer elements into a[][]
    void input()
    {
        Scanner sc = new Scanner(System.in);
        for (int i = 0; i < m; i++)
            for (int j = 0; j < n; j++)
                a[i][j] = sc.nextInt();
    }

    // arranges x[] in ascending order using insertion sort
    void ascEven(int x[])
    {
        for (int i = 1; i < x.length; i++)
        {
            int key = x[i];
            int j = i - 1;
            while (j >= 0 && x[j] > key)
            {
                x[j + 1] = x[j];
                j--;
            }
            x[j + 1] = key;
        }
    }

    // arranges x[] in descending order using insertion sort
    void dscOdd(int x[])
    {
        for (int i = 1; i < x.length; i++)
        {
            int key = x[i];
            int j = i - 1;
            while (j >= 0 && x[j] < key)
            {
                x[j + 1] = x[j];
                j--;
            }
            x[j + 1] = key;
        }
    }

    // sorts each row: even (1-indexed) row positions ascending, odd row positions descending
    void arrange()
    {
        for (int i = 0; i < m; i++)
        {
            int row[] = new int[n];
            for (int j = 0; j < n; j++)
                row[j] = a[i][j];
            if ((i + 1) % 2 == 0)
                ascEven(row);
            else
                dscOdd(row);
            for (int j = 0; j < n; j++)
                a[i][j] = row[j];
        }
    }

    // displays the original array, then arranges it and displays the sorted array
    void display()
    {
        System.out.println("Before sort:");
        for (int i = 0; i < m; i++)
        {
            for (int j = 0; j < n; j++)
                System.out.print(a[i][j] + "\t");
            System.out.println();
        }
        arrange();
        System.out.println("After sort:");
        for (int i = 0; i < m; i++)
        {
            for (int j = 0; j < n; j++)
                System.out.print(a[i][j] + "\t");
            System.out.println();
        }
    }

    public static void main(String args[])
    {
        Scanner sc = new Scanner(System.in);
        System.out.print("Row=");
        int row = sc.nextInt();
        System.out.print("Column=");
        int col = sc.nextInt();
        Mix_sort obj = new Mix_sort(row, col);
        System.out.println("Enter the array elements");
        obj.input();
        obj.display();
    }
}