ISC COMPUTER SCIENCE QUESTION PRACTICAL PAPER 2019 | QUESTION NUMBER 2 | Follow on youtube for more |

import java.util.*;
public class qstn_2
{
public static void main(String[] args)
{
Scanner sc = new Scanner(System.in);
System.out.println("Enter the number of elements");
int n = sc.nextInt();

if(n<=2||n>=10)
{
System.out.println("MATRIX SIZE OUT OF RANGE");
System.exit(0);
}

int a[] =new int[n];
//Taking array input
System.out.println("ENTER ELEMENTS OF SINGLE DIMENSIONAL ARRAY:");
for(int i=0;i<n;i++)
{
a[i] = sc.nextInt();
}

//sorting the array elements

int temp = 0;
for(int i=0;i<n;i++)
{
for(int j=0;j<n;j++)
{
if(a[i]<a[j])
{
temp = a[i];
a[i] = a[j];
a[j] = temp;
}
}
}

// Displaying the sorted array
System.out.print("\nSORTED ARRAY: ");
for(int i=0;i<n;i++)
{
System.out.print(a[i]+" ");
}

System.out.println();
int row = n;
int column = n;
int position = 0;

System.out.println("\nFILLED MATRIX");
for(int i=0;i<row;i++)
{
for(int j=0;j<column;j++)
{
System.out.print(a[j]+" ");
}
for(int j=0;j<position;j++)
{
System.out.print(a[j]+" ");
}
System.out.println();
position++;
column--;
}
}
}

ISC COMPUTER SCIENCE QUESTION PRACTICAL PAPER 2018 | QUESTION NUMBER 2 | Follow on youtube for more |

import java.util.Scanner;
public class qstn_2
{
public static void sort(int a[])
{
int temp = 0;
for(int i =0;i<a.length;i++)
{
for(int j =0;j<a.length;j++)
{
if(a[i]<a[j])
{
temp = a[i];
a[i] = a[j];
a[j] = temp;
}
}
}

for(int i =0;i<a.length;i++)
{
System.out.print(a[i]+" ");
}
System.out.println();
}
public static void main(String[] args)
{
Scanner sc = new Scanner(System.in);
System.out.println("Enter the matrix size");
System.out.print(" M = ");
int m =  sc.nextInt();
System.out.print(" N = ");
int n = sc.nextInt();
int input[][]  = new int[m][n];

// boundary case
if(n<=2||n>=10||m<=2||m>=10)
{
System.out.println("MATRIX SIZE OUT OF RANGE");
System.exit(0);
}

System.out.println("Enter elements of the matrix");
for(int i=0;i<m;i++)
{
for(int j=0;j<n;j++)
{
input[i][j] = sc.nextInt();
}
}
System.out.println("ORIGINAL MATRIX");
for(int i=0;i<m;i++)
{
for(int j=0;j<n;j++)
{
System.out.print(input[i][j]+" ");
}
System.out.println();

}


int insert = 0;
System.out.println("\nMATRIX AFTER SORTING ROWS");
for(int i=0;i<m;i++)
{
int arr[] = new int[n];
for(int j=0;j<n;j++)
{
arr[insert++] = input[i][j];
}
sort(arr);
insert = 0;
}
sc.close();
}
}

ISC COMPUTER SCIENCE QUESTION PRACTICAL PAPER 2017| QUESTION NUMBER 2 | Follow on YOUTUBE for more |

import java.util.Scanner;
public class qstn_2
{
public static void main(String[] args)
{
Scanner sc = new Scanner(System.in);
System.out.println("Enter the number of participants");
int n = sc.nextInt();

if(n<3 || n>11)
{
System.out.println("INPUT SIZE OUT OF RANGE");
System.exit(0);
}

String a[][] = new String[n][5];
for(int i=0;i<n;i++)
{
System.out.println("Participants "+(i+1));
for(int j=0;j<5;j++)
{

a[i][j] = sc.next();

}

}
System.out.println("\nKey : ");
String answer[] = new String[5];
for(int i=0;i<5;i++)
{
answer[i] = sc.next();
}

int score[] = new int[5];
int count  = 0;
int insert = 0;
int max = 0;
for(int i=0;i<n;i++)
{
for(int j=0;j<5;j++)
{
if(a[i][j].equalsIgnoreCase(answer[j]))
{
count++;
}
}

if(max<count)
max = count;

score[insert++] = count;
count=0;


}
System.out.println();
for(int i = 0;i<n;i++)
{
System.out.println("Participants "+(i+1)+" = "+score[i]);
}

System.out.println("\nHighest Score :");

for(int i = 0;i<n;i++)
{
if(max==score[i])
System.out.println("Participant "+(i+1));

}
}
}

ISC COMPUTER SCIENCE QUESTION PRACTICAL PAPER 2017| QUESTION NUMBER 3 | Follow on YOUTUBE for more |

import java.util.*;
public class qstn_3
{
public static void main(String[] args)
{
Scanner sc  = new Scanner(System.in);

//Taking user input
System.out.println("Enter the sentence");
String s = sc.nextLine();

//For lowercase characters
String low = "abcdefghijklmnopqrstuvwxyzabcdefghijklm";

//For Uppercase characters
String cap = "ABCDEFGHIJKLMNOPQRSTUVWXYZABCDEFGHIJKLM";

//Taking the length of input string
int length = s.length();

//To check for the boundary condition
if(length<4||length>99)
{
System.out.println("INVALID LENGTH");
System.exit(0);
}
//For the new word
String new_word = "";

for(int i=0;i<length;i++)
{
//Extracting
char c = s.charAt(i);

//Checking for the uppercase character
if(Character.isUpperCase(c))
{
//To get the position of the character
//so that you can encode it.
for(int j = 0;j<cap.length();j++)
{

char c1 = cap.charAt(j);

//To compare both the characters
//to check if they are equal
if(c==c1)
{

//Increasing the character by 13 position
char lower_case = cap.charAt(j+13);

//Storing the new character
new_word+=lower_case;//new_word = new_word+lower_case;
break;
}
}
}

//Checking for the lowercase character
else if(Character.isLowerCase(c))
{
//To get the position of the character
//so that you can encode it.
for(int j = 0;j<low.length();j++)
{
char c1 = low.charAt(j);

//To compare both the characters
//to check if they are equal
if(c==c1)
{

//Increasing the character by 13 position
char upper_case = low.charAt(j+13);

//Storing the new character
new_word+=upper_case;
break;
}
}
}

//For exclaimation mark character
else if(c=='!')
{
new_word+="?";
}

//For any other characters
else
{
new_word+=c;
}
}

//Result output
System.out.println("\nThe cipher text is:");
System.out.println(new_word);
}
}

ISC COMPUTER SCIENCE QUESTION PRACTICAL PAPER 2017| QUESTION NUMBER 1 | Follow on youtube for more |

import java.util.*;
public class qstn_1
{
public static void main(String[] args)
{
Scanner sc = new Scanner(System.in);
System.out.println("Enter the input ");
int n = sc.nextInt();
int n1 = n;
int count = 0;
if(n>1000)
{
System.out.println("INVALID INPUT");
System.exit(0);
}

if(n>=48)
{
int div = n/48;
n = n-div*48;
count = count + div;
}

if(n>=24)
{
int div = n/24;
n = n-div*24;
count = count + div;
}

if(n>=12)
{
int div = n/12;
n = n-div*12;
count = count + div;
}

if(n>=6)
{
int div = n/6;
n = n-div*6;
count = count + div;
}

System.out.println("Remaining boxes = "+n);
if(n!=0)
{
count++;
}
System.out.println("Total number of boxes = "+n1);
System.out.println("Total number of cartons =  "+count);

}
}

ISC COMPUTER SCIENCE QUESTION PRACTICAL PAPER 2018 | QUESTION NUMBER 3 | Follow on youtube for more |

import java.util.*;
public class qstn_3
{
public static void main(String[] args)
{
Scanner sc = new Scanner(System.in);
System.out.println("Enter the number of words");
int n = sc.nextInt();

//To shift the command to next line as after an integer input when we take a string
        // input the command does not shift to next line and is rather skipped.
        //It does not read the newline character in your input created by hitting "Enter,"
sc.nextLine();

//Boundary cases
if(n<2 && n>9)
{
System.out.println("Invalid Input");
System.exit(0);
}
// word array
String s[] = new String[n];

// length array
int length[] = new int[n];

for(int i = 0;i<n;i++)
{

// taking the string input 
s[i] = sc.nextLine();



// length of each word stored in the array
length[i] = s[i].length();
}
int j = 0;
String k = "";
int flag = 0;

// infinite loop as we don't know the length of
// maximum word.
while(true)
{

// Running the loop for each word
for(int i = 0;i<n;i++)
{

// This will check if the length is not zero
if(length[i]!=0)
{

// We extract the character
char c = s[i].charAt(j);

//We store the character in the variable with a space
k = k+c+" ";

// We decrease the length
length[i]--;

// A check variable for exit condition
flag++;
}

// If there are no character, we just add two spaces.
else
{
k = k+"  ";
}
}
// We increase the character position
j++;

// Display of the words
System.out.println(k);

// Erasing the word for next loop
k="";

//Exit condition when no more character in any word
if(flag==0)
{
System.exit(0);
}

//Initializing the flag to zero for next loop
flag = 0;
}
}
}

ISC COMPUTER SCIENCE QUESTION PRACTICAL PAPER 2018 | QUESTION NUMBER 1 | GOLDBACH NUMBER | Follow on youtube for more |

import java.util.*;
public class qstn_1
{
public static int check(int n,int pos,int input)
{

int result=0;
int prime[] = {2,3,5,7,11,13,17,19,23,29,31,37,41,43,47};
for(int i = pos;i<prime.length;i++)
{
int sum = n+prime[i];
if(sum==input)
{
result= prime[i];
break;
}
sum = 0;
}
return result;
}
public static void main(String[] args)
{
Scanner sc = new Scanner(System.in);
System.out.println("Enter the number");
int n = sc.nextInt();
// boundary conditions
if(n<9 || n>50)
{
System.out.println("INVALID INPUT. NUMBER OUT OF RANGE.");
System.exit(0);
}
if(n>1 && n%2!=0)
{
System.out.println("INVALID INPUT. NUMBER IS ODD.");
System.exit(0);
}
int prime[] = {2,3,5,7,11,13,17,19,23,29,31,37,41,43,47};
int n1[] = new int[10];
int n2[] = new int[10];
int ins1 = 0,ins2 = 0;
int length = prime.length;
int pos = 0;
int result=0;
int pos2 = 0;
while(length!=0)
{
pos2 = pos;
result = check(prime[pos],pos++,n);
if(result!=0)
{
n1[ins1++] = prime[pos2];// number sending
n2[ins2++] = result; // result from function
}
length--;
}
for(int i=0;i<ins1;i++)
{
System.out.println(n1[i]+", "+n2[i]);
}
}
}

ISC COMPUTER SCIENCE QUESTION PRACTICAL PAPER 2019 | QUESTION NUMBER 1 | Follow on youtube for more |

                                   


Question 1

Design a program to accept a day number (between 1 and 366), year (in 4 digits) from the user
to generate and display the corresponding date. Also, accept ‘N’ (1 <= N <= 100) from the
user to compute and display the future date corresponding to ‘N’ days after the generated date.
Display an error message if the value of the day number, year and N are not within the limit or
not according to the condition specified.

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

Example 1
INPUT: DAY NUMBER: 255
YEAR: 2018
DATE AFTER (N DAYS): 22
OUTPUT: DATE: 12 TH SEPTEMBER, 2018
DATE AFTER 22 DAYS: 4 TH OCTOBER, 2018

Example 2
INPUT: DAY NUMBER: 360
YEAR: 2018
DATE AFTER (N DAYS): 45
OUTPUT: DATE: 26 TH DECEMBER, 2018
DATE AFTER 45 DAYS: 9 TH FEBRUARY, 2019

Example 3
INPUT: DAY NUMBER: 500
YEAR: 2018
DATE AFTER (N DAYS): 33
OUTPUT: DAY NUMBER OUT OF RANGE.
Example 4

INPUT: DAY NUMBER: 150
YEAR: 2018
DATE AFTER (N DAYS): 330
OUTPUT: DATE AFTER (N DAYS) OUT OF RANGE.

-----------------------------------------------------CODE-------------------------------------------------------

import java.util.*;
public class qstn_1
{
static int[] daycheck(int day_number, int year)
{

int dd[] = {31,28,31,30,31,30,31,31,30,31,30,31};
  boolean leap = false;
        if(year % 4 == 0)
        {
            if( year % 100 == 0)
            {
                // year is divisible by 400, hence the year is a leap year
                if ( year % 400 == 0)
                    leap = true;
                else
                    leap = false;
            }
            else
                leap = true;
        }
        else
            leap = false;
        if(leap!=false)
        dd[1] = 29;
        int res = day_number;
        int flag = 0;
        int result [] = {0,0};
        while(res>31)
        {
        res = res-dd[flag++];
        }
        result[0] = res;//date
        result[1] = flag++;//month
       return result;
}
static int[] after_check(int day,int day_after,int year,int month)
{
int dd[] = {31,28,31,30,31,30,31,31,30,31,30,31};
  boolean leap = false;
        if(year % 4 == 0)
        {
            if( year % 100 == 0)
            {
                // year is divisible by 400, hence the year is a leap year
                if ( year % 400 == 0)
                    leap = true;
                else
                    leap = false;
            }
            else
                leap = true;
        }
        else
            leap = false;
        if(leap!=false)
        dd[1] = 29;
        int res = day;
        int flag = month--;//as as array index starts from 0
     
     
        int left = dd[flag]-day;
        if(left==day_after)
        day+=dd[flag];
        else if(left<day_after)
        {
        day_after= day_after -left;
        day = dd[flag++];// Giving the maximum day of the month
        }
        else if(left>day_after)
        {
        day +=day_after;// adding the after day to  current day
        day_after = 0;
        }
        int yc = 0;
        //for change in year
        if(flag==12)
        {
        flag=0;
        yc = 1;
        }
   
        while(day_after!=0)
        {
        // if there is a month change so year has to change
        if(flag==11&&day_after!=0)
        {
        flag=0;
        yc = 1;
        }
        // when finally day after is less than the days in that particular month
        if(day_after<dd[flag])
        {
        day = day_after;
        day_after = 0;
        }
        //when day afer is exactly as number of days in month
        else if(day_after==dd[flag])
        {
        day = day_after;
        day_after = 0;
        }
        //when day after is greater than the number of days in month we add the days
        //we subtract the day after from number of days in the month and also
        //add the days for calculation in the current period.
        else if(day_after>dd[flag])
        {
        day = day_after-dd[flag];
        day_after-=dd[flag++];
        }        
        }
        if(yc==1)
        year +=1;
        else
        year = year;
     
        int result[] = new int[3];
        result[0] = day;
        result[1] = flag;// month
        result[2] = year;
        return result;
}
public static void main(String[] args)
{
Scanner sc  = new Scanner(System.in);
System.out.println("Enter the day number");
int n = sc.nextInt();
System.out.println("Enter the year");
int y = sc.nextInt();
System.out.println("Enter the date after (N days) ");
int a = sc.nextInt();
if(n<1 || n>366)
{
System.out.println("DAY NUMBER OUT OF RANGE");
System.exit(0);
}
if(a<1 || a>100)
{
System.out.println("DATE AFTER (N DAYS) OUT OF RANGE");
System.exit(0);
}
String year = Integer.toString(y);
int length = year.length();
if(length!=4)
{
System.out.println("INVALID YEAR");
System.exit(0);
}
int day[] = daycheck(n,y);
//System.out.println(day[0]);
int after[] =after_check(day[0],a,y,day[1]);
String mon1 = "",mon2 ="";
String month[] = {"JANUARY","FEBRUARY","MARCH","APRIL","MAY","JUNE","JULY","AUGUST","SEPTEMBER","OCTOBER","NOVEMBER","DECEMBER"};

if(day[0]>3)
{
mon1 = "TH";

}
if( after[0]>3)
{
mon2="TH";
}

if(day[0]==1)
{
mon1 = "ST";

}
if(after[0]==1)
{
mon2 = "ST";
}
if(day[0]==2)
{
mon1 = "ND";

}
if(after[0]==2)
{
mon2 = "ND";
}
if(day[0]==3)
{
mon1 = "RD";

}
if (after[0]==3)
{
mon2 = "RD";
}
// else
// {
// mon1 = "TH";
// mon2 = "TH";
// }
System.out.println(day[0]+" "+mon1+" "+month[day[1]]+","+y );
System.out.println(after[0]+" "+mon2+" "+month[after[1]]+","+after[2]);

}

}

ISC COMPUTER SCIENCE QUESTION PRACTICAL PAPER 2019 | QUESTION NUMBER 3 | Follow on youtube for more |

3. Write a program to accept a sentence which may be terminated by either ‘.’ , ‘?’ or
‘!’ only. The words are to be separated by a single blank space and are in UPPER
CASE.
Perform the following tasks:
(a) Check for the validity of the accepted sentence.

(b) Convert the non-palindrome words of the sentence into palindrome words by
concatenating the word by its reverse (excluding the last character).
Example: The reverse of the word HELP would be LEH (omitting the last
alphabet) and by concatenating both, the new palindrome word is
HELPLEH. Thus, the word HELP becomes HELPLEH.
Note: The words which end with repeated alphabets, for example ABB
would become ABBA and not ABBBA and XAZZZ becomes
XAZZZAX.
[Palindrome word: Spells same from either side. Example: DAD, MADAM etc.]

(c) Display the original sentence along with the converted sentence.
Test your program for the following data and some random data:

Example 1
INPUT: THE BIRD IS FLYING.
OUTPUT: THE BIRD IS FLYING.
THEHT BIRDRIB ISI FLYINGNIYLF

Example 2
INPUT: IS THE WATER LEVEL RISING?
OUTPUT:  IS THE WATER LEVEL RISING?
                  ISI THEHT WATERETAW LEVEL RISINGNISIR

Example 3
INPUT: THIS MOBILE APP LOOKS FINE.
OUTPUT: THIS MOBILE APP LOOKS FINE.
                  THISIHT MOBILELIBOM APPA LOOKSKOOL FINENIF

Example 4 INPUT: YOU MUST BE CRAZY#
OUTPUT: INVALID INPUT

import java.util.*;
public class qstn_2
{
static String palincheck(String word)
{
int flag = 0;
String s1 = "",s2 = "",s3 = "";
String result = "";
// Reversing the word.
for(int i=word.length()-1;i>=0;i--)
{
char c = word.charAt(i);
s1 = s1+c;
}
//Compare the reverse word with original word.
if(s1.equalsIgnoreCase(word))
{
flag=1;
}

//When the word is not palindrome.
if(flag!=1)
{
int l  = word.length();
char last_char = word.charAt(l-1);
int dupli_length = 0;
int count = 0;

//To get the length when the word has repeated
//character ending
for(int i = l-1;i>=0;i--)
{
char c1 = word.charAt(i);
if(last_char==c1)
{
count++;
dupli_length = i;
}
//So that only last repeated character 
else
break;

}
//Change the length when the characters
//have repeated ending.
if(count<=1)
{
dupli_length  = l;
}
//We increase it  by 1 for array indexing purposes.
if(count>1)
{
dupli_length++;
}

for(int i = 0;i<dupli_length-1;i++) // hello hell lleh
{
char c = word.charAt(i);
s2=c+s2;
}
s3 = word+s2;
result = s3;
}
return result;
}
public static void main(String[] args)
{
Scanner sc = new Scanner(System.in);
System.out.println("Enter the sentence");
String s = sc.nextLine();
int l = s.length();
String words[] = new String[100];
String k = "";
int ins = 0;
if(s.charAt(l-1)=='?'||s.charAt(l-1)=='.'||s.charAt(l-1)=='!')
{
for(int i = 0;i<l;i++)
{
char c = s.charAt(i);
if(c==' '||c=='?'||c=='.'||c=='!')
{
words[ins++] = k;
k = "";
}
else 
{
k = k+c;
}
}
for(int i = 0;i<ins;i++)
{
String w = palincheck(words[i]);
words[i] = w;
}
System.out.println(s);
for(int i =0;i<ins;i++)
System.out.print(words[i]+" ");
}
else
System.out.println("INVALID INPUT");
}
}

Smith Number | Programming | Eclipse JAVA | Follow on Youtube for more

import java.util.Scanner;
public class smith_number
{
public static int sum(int number)
{
int sum = 0;
while(number!=0)
{
int mod = number%10;
sum = sum+mod;
number = number/10;
}
return sum;
}
public static void main(String[] args)
{
Scanner sc = new Scanner(System.in);
System.out.println("Enter the number");
int n = sc.nextInt();
int n1 = n;
int check = 2;
int result1 = sum(n);
int result2 = 0;
while(n!=0)
{
if(n%check==0)
{
n = n/check;
result2  = result2+sum(check);
}
else if(check>n1)
break;
else
check++;
}
if(result1==result2)
System.out.println(n1+" is a Smith Number");
else
System.out.println(n1+" is not a Smith Number");
sc.close();
}
}
/*
Input  : n = 4
Output : Yes
Prime factorization = 2, 2  and 2 + 2 = 4
Therefore, 4 is a smith number

Input  : n = 6
Output : No
Prime factorization = 2, 3  and 2 + 3 is
not 6. Therefore, 6 is not a smith number

Input   : n = 666
Output  : Yes
Prime factorization = 2, 3, 3, 37 and
2 + 3 + 3 + (3 + 7) = 6 + 6 + 6 = 18
Therefore, 666 is a smith number

Input   : n = 13
Output  : No
Prime factorization = 13 and 13 = 13,
But 13 is not a smith number as it is not
a composite number
*/

Keith Number | Programming | Eclipse JAVA | Follow on Youtube for more

import java.util.*;
public class keith_number
{
public static void main(String[] args)
{
Scanner sc = new Scanner(System.in);
System.out.println("Enter the number");
String s = sc.next();//taking it as String input
int length = s.length();//taking the string length
int n1 = Integer.parseInt(s);//converting the string into integer
int n2 = n1;//making copy of the number for digit separation operation
int a[] = new int[100];
int insert = length;
while(n2!=0)
{
int mod = n2%10;
a[--insert] = mod;//each digits are stored in array separately
n2 = n2/10;
}
int flag = length;
int sum = 0;
int count= 0;
while(true)//Going for infinite loop
{
for(int i=count;i<flag;i++)//adding last n numbers, where n stands for number of digits
{
sum += a[i];
}
if(sum>n1)//if the sum exceeds the original number, we exit the program
{
System.out.println(n1+" is not a Keith Number");
System.exit(0);
}
if(sum==n1)//if sum is equal to number, than it is a Keith number
{
System.out.println(n1+" is a Keith Number");
System.exit(0);
}
a[flag++] = sum;//adding the sum back to the array, and length of array iteration also exceeds
count++;//increasing the array starting value
sum=0;//initializing the sum back to zero
}
}
}
/*
A n digit number x is called Keith number if it appears in a special sequence
 (defined below) generated using its digits. The special sequence has first n terms
 as digits of x and other terms are recursively evaluated as sum of previous n terms.

The task is to find if a given number is Keith Number or not.

Examples:

Input : x = 197
Output : Yes
197 has 3 digits, so n = 3
The number is Keith because it appears in the special
sequence that has first three terms as 1, 9, 7 and
remaining terms evaluated using sum of previous 3 terms.
1, 9, 7, 17, 33, 57, 107, 197, .....

Input : x = 12
Output : No
The number is not Keith because it doesn't appear in
the special sequence generated using its digits.
1, 2, 3, 5, 8, 13, 21, .....

Input : x = 14
Output : Yes
14 is a Keith number since it appears in the sequence,
1, 4, 5, 9, 14, ...
 */

EMIRP Number | Programming | Eclipse JAVA | Follow on Youtube for more

import java.util.Scanner;
public class EMIRP_number
{
public static boolean check(int n)
{
int count=0;
for(int i=1;i<n;i++)
{
if(n%i==0)
count++;
}
if(count==1)
return true;
return false;
}
public static void main(String[] args)
{
Scanner sc = new Scanner(System.in);
System.out.println("Enter a number");
int n = sc.nextInt();
int n1 = n;
boolean b1 = check(n);
int rev = 0;
while(n!=0)
{
int mod = n%10;
rev  = rev*10+mod;
n/=10;
}
boolean b2 = check(rev);
if(b1==true && b2==true)
System.out.println(n1+" is an EMIRP number");
else
System.out.println(n1+" is not an EMIRP number");
}
}
/*
Input : n = 13
Output : 13 is Emirp!
Explanation :
13 and 31 are both prime numbers.
Thus, 13 is an Emirp number.

Input : n = 27
Output : 27 is not Emirp.
*/

Mersenne Number | Programming | Eclipse JAVA | Follow on Youtube for more

import java.util.*;
public class mersenne_number
{
static boolean prime_check(double n)
{
int count = 0;
for(int i=1;i<n;i++)
{
if(n%i==0)
count++;
}
if(count==1)
return true;
else
return false;
}
public static void main(String[] args)
{
Scanner sc = new Scanner(System.in);
System.out.println("Enter till where mersenne number is to be generated");
int n = sc.nextInt();
double a[] = new double[100];// storing the answers
int count = 0;
for(int i=2;i<n;i++)
{
double number = Math.pow(2, i)-1; //   2^k-1
if(number<=n)
{
boolean result = prime_check(number);
if(result==true)
{
a[count++]  =  number;
}
}
else
{
break;
}
}
if(count!=0)
{
System.out.println("The Mersenne number are as follows :");
for(int i=0;i<count;i++)
{
System.out.println(a[i]);
}
}
else
System.out.println("There are no mersenne number");
}
}
/*
Mersenne Prime is a prime number that is one less than a power of two. In other words,
any prime is Mersenne Prime if it is of the form 2^k-1 where k is an integer greater than
or equal to 2. First few Mersenne Primes are 3, 7, 31 and 127.

The task is print all Mersenne Primes smaller than an input positive integer n.
Examples:

Input: 10
Output: 3 7
3 and 7 are prime numbers smaller than or
equal to 10 and are of the form 2^k-1

Input: 100
Output: 3 7 31
 */

Pronic Number | Programming | Eclipse JAVA | Follow on Youtube for more

import java.util.*;

class Pronic_Number

{

    public static void main1(String []args)

    {

        int num,count=0,d;

        Scanner sc=new Scanner(System.in);

        System.out.println("Enter the number");

        num=sc.nextInt();

        for( int i=1;i<(num/2);i++)//6

        {

            d=i*(i+1);

            if(d==num)

            {

            count=count+1;

            break;

             }

            else

            d=0;

        }

        if(count>0)

        System.out.println(num+" is a pronic number");

        else

        System.out.println(num+" is not a pronic number");

    }

}

/*

 A pronic number is a something which is a product of 2 consecutive numbers.

 

Input  : 6

Output : Pronic Number

Explanation: 6 = 2 * 3 i.e 6 is a product

of two consecutive integers 2 and 3.

Input :56

Output :Pronic Number

Explanation: 56 = 7 * 8 i.e 56 is a product

of two consecutive integers 7 and 8.

Input  : 8

Output : Not a Pronic Number

Explanation: 8 = 2 * 4 i.e 8 is a product of

2 and 4 which are not consecutive integers.

*/

Harshad Number | Programming | Eclipse JAVA | Follow on Youtube for more

import java.util.*;
// Harshad number is also called niven number
public class harshad_number
{
public static void main(String[] args)
{
Scanner sc = new Scanner(System.in);
System.out.println("Enter the number to be checked");
int n  = sc.nextInt();
int n1 = n;
int sum = 0;
while(n1!=0)
{
int rem  = n1%10;
sum  = sum + rem;
n1 = n1/10;
}
if(n%sum==0)
{
System.out.println(n+" is a harshad number");
}
else
{
System.out.println(n+" is not a harshad number");
}
}
}
/*
Input: 3
Output: 3 is a Harshad Number

Input: 18
Output: 18 is a Harshad Number

Input: 15   
Output: 15 is not a Harshad Number


54       9
*/

Duck Number | Programming | Eclipse JAVA | Follow on Youtube for more

Code:
import java.util.Scanner;
public class duck_number
{
public static void main(String[] args)
{
Scanner sc = new Scanner(System.in);
System.out.println("Enter the number to be checked");
String s = sc.next();
char c = s.charAt(0);
if(c=='0')
System.out.println(s+" is not a duck number");
else
{
int count = 0;
for(int i=1;i<s.length();i++)
{
c = s.charAt(i);
if(c=='0')
count++;
}
if(count>0)
System.out.println(s+" is a duck number");
else
System.out.println(s+" is not a duck number");
}
}
}
/*
 Input : 707069
Output : It is a duck number.
Explanation: 707069 does not contains zeros at the beginning.

Input : 02364
Output : It is not a duck number.
Explanation: in 02364 there is a zero at the beginning of the number.
 */

Data Types in JAVA | Understanding Variables | UNICODE | LIKE SHARE AND SUBSCRIBE |

This video explains about primitive and non primitive data types in java.
It explains all 8 types of data types:
the arithmetic types:

A. The integral types:
1. byte
2. short
3. int
4. long

B. The floating-point types:
5. float
6. double

C. boolean, the type whose values are either true or false

D. char, the character type whose values are 16-bit Unicode characters

It also explains about Local, Global and Static variable type.

Downloading and Installing Eclipse | Like Share Subscribe|

This video shows you complete process of how to download and install Eclipse.
 It works everytime.

Eclipse Download:  https://www.eclipse.org/downloads/

Please Like Share and Subscribe..

Running program in Command Prompt using Text File | Follow Youtube for More |

This video shows you how you can run simple java program using text file and command prompt. It also teaches you basic commands of command prompt.

Java Environment Setup(100% working)| Running text files from Command Prompt| Susbscribe to Youtube for more

The video shows you how to setup java path, so that you can run java program through command prompt that is using a text file.

Link for Jdk : https://www.oracle.com/technetwork/java/javase/downloads/jdk11-downloads-5066655.html

Disarium Number | Programming | Eclipse JAVA | Follow on Youtube for more

import java.util.*;
public class disarium_number
{
static boolean check(int n1)
{
//Reversing the number
String s = Integer.toString(n1),s2 = "";
//Reverse loop
for(int i=0;i<s.length();i++)
{
char c = s.charAt(i);
s2 = c+s2;// reverse number in string format
}
int n = Integer.parseInt(s2);
double sum = 0;
int power = 1;
//checking the number
while(n!=0)//531
{
int rem = n%10;
sum = sum+Math.pow(rem,power);
n = n/10;
power++;
}
System.out.println("The sum is "+sum+" and Original Number is "+n1);
if(sum==n1)
return true;
else
return false;
}
public static void main(String[] args)
{
Scanner sc = new Scanner(System.in);
//taking user input
System.out.println("Enter the number to be checked");
int n = sc.nextInt();
//sending the number to be checked
boolean b = check(n);
if(b==true)
System.out.println(n+" is a disarium number");
else
System.out.println(n+" is not a disarium number");
sc.close();
}
}

/*
Input   : n = 135
Output  : Yes
1^1 + 3^2 + 5^3 = 135
Therefore, 135 is a Disarium number

Input   : n = 89
Output  : Yes
8^1+9^2 = 89
Therefore, 89 is a Disarium number

Input   : n = 80
Output  : No
8^1 + 0^2 = 8
 */

Automorphic Number Programming | In JAVA | Eclipse |

import java.util.Scanner;
public class automorphic_number
{
public static void main(String[] args)
{
Scanner sc = new Scanner(System.in);
System.out.println("Enter the number to be checked ");
int n  = sc.nextInt();
int square  = n*n;     
System.out.println(square);
String s = Integer.toString(n);
int l = s.length();           
double power = Math.pow(10, l);
double rem = square%power;
if(rem==n)
System.out.println(n+" is an automorphic number");
else
System.out.println(n+" is not an automorphic number");
sc.close();
}
}
/*
Input  : N = 76
Output : Automorphic
Explanation: As 76*76 = 5776

Input  : N = 25
Output : Automorphic
As 25*25 = 625

Input : N = 7
Output : Not Automorphic
As 7*7 = 49
 5
 25

 */

Kaprekar Number | Programming | Eclipse JAVA | Follow on Youtube for more

Code:
import java.util.*;
public class kaprekar_number
{
static int check(int square,int n)
{
String s = Integer.toString(square);
int l = s.length();
if(l%2==0) // when square has even digits
{
String s1 = s.substring(0,l/2);//20
int n1 = Integer.parseInt(s1);
String s2 =s.substring(l/2,l); //25
int n2 = Integer.parseInt(s2);
System.out.println(s1+"  "+s2);
if((n1+n2)==n&& n1>0 &&n2>0)
return 1;
}
else // When the square has odd digits
{
String s1 = s.substring(0,l/2+1);
int n1 = Integer.parseInt(s1);
String s2 =s.substring(l/2+1,l);
int n2 = Integer.parseInt(s2);
System.out.println(s1+"  "+s2);
if((n1+n2)==n && n1>0 &&n2>0)
return 1;
String s3 = s.substring(0,l/2);
int n3 = Integer.parseInt(s3);
String s4 =s.substring(l/2,l);
int n4 = Integer.parseInt(s4);
System.out.println(s3+"  "+s4);
if(((n3+n4)==n)&& n3>0 &&n4>0)
return 1;
}

return 0;
}
public static void main(String[] args)
{
Scanner sc = new Scanner(System.in);
System.out.println("Enter the number to be checked");
int n = sc.nextInt();
int square = n*n;
System.out.println(square);
int result  = check(square,n);
if(result ==1)
System.out.println(n+" is a kaprekar number");
else
System.out.println(n+" is not a kaprekar number");
sc.close();
}
}


/*
Input :  n = 45
Output : Yes
Explanation : 45^2 = 2025 and 20 + 25 is 45

Input : n = 13
Output : No
Explanation : 13^2 = 169. Neither 16 + 9 nor 1 + 69 is equal to 13

Input  : n = 297
Output : Yes
Explanation:  297^2 = 88209 and 88 + 209 is 297 and 882+09 = 891

Input  : n = 10
Output : No
Explanation:  10^2 = 100. It is not a Kaprekar number even if
sum of 10 + 0 is 10. This is because of the condition that
none of the parts should have value 0.
 */