Objects - ISC Class 12 Computer Science Questions with Answers, Page 3

import java.util.Scanner;

class MatRev
{
    int arr[][];
    int m, n;

    MatRev(int mm, int nn)
    {
        m = mm;
        n = nn;
        arr = new int[m][n];
    }

    void fillarray()
    {
        Scanner sc = new Scanner(System.in);
        System.out.println("Enter " + (m * n) + " elements:");
        for (int i = 0; i < m; i++)
            for (int j = 0; j < n; j++)
                arr[i][j] = sc.nextInt();
    }

    int reverse(int x)
    {
        int rev = 0;
        while (x != 0)
        {
            rev = rev * 10 + x % 10;
            x = x / 10;
        }
        return rev;
    }

    void revMat(MatRev P)
    {
        for (int i = 0; i < m; i++)
            for (int j = 0; j < n; j++)
                arr[i][j] = reverse(P.arr[i][j]);
    }

    void show()
    {
        for (int i = 0; i < m; i++)
        {
            for (int j = 0; j < n; j++)
                System.out.print(arr[i][j] + "\t");
            System.out.println();
        }
    }

    public static void main(String args[])
    {
        MatRev A = new MatRev(3, 3);
        A.fillarray();
        MatRev B = new MatRev(3, 3);
        B.revMat(A);
        System.out.println("Original matrix:");
        A.show();
        System.out.println("Reversed matrix:");
        B.show();
    }
}

import java.util.Scanner;
import java.util.StringTokenizer;

class Capital
{
    String sent;
    int freq;

    Capital()
    {
        sent = "";
        freq = 0;
    }

    void input()
    {
        Scanner sc = new Scanner(System.in);
        System.out.println("Enter a sentence:");
        sent = sc.nextLine();
    }

    boolean isCap(String w)
    {
        char ch = w.charAt(0);
        if (ch >= 'A' && ch <= 'Z')
            return true;
        else
            return false;
    }

    void display()
    {
        StringTokenizer st = new StringTokenizer(sent, " ,.");
        freq = 0;
        while (st.hasMoreTokens())
        {
            String w = st.nextToken();
            if (isCap(w))
                freq++;
        }
        System.out.println("Sentence : " + sent);
        System.out.println("Frequency of words beginning with a capital letter : " + freq);
    }

    public static void main(String args[])
    {
        Capital ob = new Capital();
        ob.input();
        ob.display();
    }
}

import java.util.Scanner;

class Perfect
{
    int num;

    Perfect(int nn)
    {
        num = nn;
    }

    int sum_of_factors(int i)
    {
        if (i > num / 2)
            return 0;
        else if (num % i == 0)
            return i + sum_of_factors(i + 1);
        else
            return sum_of_factors(i + 1);
    }

    void check()
    {
        int s = sum_of_factors(1);
        if (s == num)
            System.out.println(num + " is a Perfect number.");
        else
            System.out.println(num + " is not a Perfect number.");
    }

    public static void main(String args[])
    {
        Scanner sc = new Scanner(System.in);
        System.out.print("Enter a number: ");
        int nn = sc.nextInt();
        Perfect ob = new Perfect(nn);
        ob.check();
    }
}

import java.util.Scanner;

class EqMat
{
    int a[][];
    int m, n;

    EqMat(int mm, int nn)
    {
        m = mm;
        n = nn;
        a = new int[m][n];
    }

    void readarray()
    {
        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();
    }

    int check(EqMat P, EqMat Q)
    {
        if (P.m != Q.m || P.n != Q.n)
            return 0;
        for (int i = 0; i < P.m; i++)
            for (int j = 0; j < P.n; j++)
                if (P.a[i][j] != Q.a[i][j])
                    return 0;
        return 1;
    }

    void print()
    {
        for (int i = 0; i < m; i++)
        {
            for (int j = 0; j < n; j++)
                System.out.print(a[i][j] + " ");
            System.out.println();
        }
    }

    public static void main(String args[])
    {
        Scanner sc = new Scanner(System.in);
        System.out.print("Enter rows and columns: ");
        int m = sc.nextInt(), n = sc.nextInt();
        EqMat A = new EqMat(m, n);
        System.out.println("Enter elements of Matrix A:");
        A.readarray();
        EqMat B = new EqMat(m, n);
        System.out.println("Enter elements of Matrix B:");
        B.readarray();
        A.print();
        B.print();
        if (A.check(A, B) == 1)
            System.out.println("The two matrices are equal.");
        else
            System.out.println("The two matrices are not equal.");
    }
}

import java.util.Scanner;

class Palin
{
    int num;      // number to be checked
    int revnum;   // reverse of the number

    Palin()
    {
        num = 0;
        revnum = 0;
    }

    void accept()
    {
        Scanner sc = new Scanner(System.in);
        System.out.print("Enter a positive number: ");
        num = sc.nextInt();
    }

    // reverses y recursively and stores the result in revnum
    int reverse(int y)
    {
        if (y == 0)
            return revnum;
        revnum = revnum * 10 + y % 10;
        return reverse(y / 10);
    }

    void check()
    {
        revnum = 0;
        reverse(num);
        if (num == revnum)
            System.out.println(num + " is a Palindrome number");
        else
            System.out.println(num + " is not a Palindrome number");
    }

    public static void main(String args[])
    {
        Palin obj = new Palin();
        obj.accept();
        obj.check();
    }
}