Computer Science Half Yearly Practical Paper Solution

Half-Yearly [Practical] Solution

$ Question 1 :

import java.util.Scanner;

class Question1

{

    Scanner S = new Scanner(System.in);

    public String noToDate(int x)

    {

        String ns="",temp="",str= "";

        int day = x/10000;

        int month = (x%10000)/100;

        int year = x%100;

        str = " "+Integer.toString(year);

        if(month<=12)

        {

            if(month==1)

            str = " January,"+str;

            if(month==2)

            str = " February,"+str;

            if(month==3)

            str = " March,"+str;

            if(month==4)

            str = " April,"+str;

            if(month==5)

            str = " May,"+str;

            if(month==6)

            str = " June,"+str;

            if(month==7)

            str = " July,"+str;

            if(month==8)

            str = " August,"+str;

            if(month==9)

            str = " September,"+str;

            if(month==10)

            str = " October,"+str;

            if(month==11)

            str = " November,"+str;

            if(month==12)

            str = " December,"+str;

        }

        else

        return "INVALID DATE";

        if((day==31)&&((month==2)||(month==4)||(month==6)||(month==9)||(month==11)))

        return "INVALID DATE";

        if((day>28)&&(month==2))

        {

            if(day>29)

            return "INVALID DATE";

            if((day==29)&&(isLeapYear(year)==false))

            return "INVALID DATE";

        }

        if((day<10)&&(day>20))

        {

            if(day%10==1)

            str = Integer.toString(day)+"st"+str;

            if(day%10==2)

            str = Integer.toString(day)+"nd"+str;

            if(day%10==3)

            str = Integer.toString(day)+"rd"+str;

        }

        else

        str = Integer.toString(day)+"th"+str;

        int o =day%10;

        if((o==4)||(o==5)||(o==6)||(o==7)||(o==8)||(o==9)||(o==10))

        str = Integer.toString(day)+"th"+str;

        str = str+"\nVALID DATE";

        return str;

    }

    public boolean isLeapYear(int x)

    {

        if((x%100)%4==0)

        return true;

        else

        return false;

    }

    public void main()

    {

        System.out.print("Enter the date in ddmmyy format : ");

        int date = S.nextInt();

        System.out.println(noToDate(date));

    }

}

$ Question 2 :

import java.util.Scanner;

class Question2

{

    Scanner S = new Scanner(System.in);

    public boolean isKeith(int n)

    {

        int no = n;

        int sum = 0;

        int d = nod(n);

        int digits[] = new int[nod(no)];

        int terms[] = new int[n];

        for(int i = nod(n)-1;i>=0;i--)

        {

            terms[i] = no%10;

            no=no/10;

        }

        while(sum<n)

        {

            sum = 0;

            for(int k =0;k<= nod(n);k++)

            sum=sum+terms[d-k];

            terms[d] = sum;

            d++;

        }

        if(sum==n)

        return true;

        else

        return false;

    }

    public void main()

    {

        System.out.println("Enter the range in which you want to find Keith Numbers :- ");

        System.out.print("Enter m : ");

        int m = S.nextInt();

        System.out.print("Enter n : ");

        int n = S.nextInt();

        if((m<10)||(n<10)||(m>n)||(m>=5000)||(n>=5000))

        System.out.println("Invalid Input");

        else

        System.out.print("Keith numbers between "+m+" and "+n+" are : ");

       

        for(int i= m;i<=n;i++)

        if(isKeith(i))

        System.out.print(i+",");

        System.out.println("\b\n");

    }

    public int nod(int no)

    {

        int result = 0;

        while(no>0)

        {

            result++;

            no=no/10;

        }

        return result;

    }

}

$ Question 3 :

import java.util.Scanner;

class Question3

{

    Scanner S = new Scanner(System.in);

    public boolean areAmicable(int x,int y)

    {

        if((sum_of_factors(x)==y)&&(sum_of_factors(y)==x))

        return true;

        else

        return false;

    }

    public int sum_of_factors(int x)

    {

        int sum = 0;

        for(int i = 1;i<x;i++)

        if(x%i==0)

        sum = sum + i;

        return sum;

    }

    public void main()

    {

        System.out.print("Number 1 : ");

        int a = S.nextInt();

        System.out.print("Number 2 : ");

        int b = S.nextInt();

        if(areAmicable(a,b))

        {

            System.out.print("Amicable Numbers\nSum of Factors of "+a+" : 1");

            for(int u = 2;u<a;u++)

            if(a%u==0)

            System.out.print("+"+u);

            System.out.println(" = "+b);

            System.out.print("Sum of Factors of "+b+" : 1");

            for(int u = 2;u<b;u++)

            if(b%u==0)

            System.out.print("+"+u);

            System.out.println(" = "+a);

        }

        else

        System.out.println("Not Amicable Numbers");

    }

}