Question

Write a Java program using while - loop to enter any integer and display how many digits in that number are perfectly divisible by 7 if the number entered is positive else find how many of the digits are divisible by 5. Find  the sum of those digits.​

Answer 1

Question:-

• Write a Java program using while - loop to enter any integer and display how many digits in that number are perfectly divisible by 7 if the number entered is positive else find how many of the digits are divisible by 5. Find  the sum of those digits.

Answer:-

package Coder;

import java.util.*;

public class Digit {

public static void main(String[] args) {

Scanner sc = new Scanner(System.in);

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

int n = sc.nextInt();

int c = 0;

if (n > 0) // To check if entered number is positive or not

{

System.out.println("Entered number is positive");

while (n != 0)

{

int d = n % 10;

if (d % 7 == 0)

c++;

n/=10;

}

System.out.println("\nNumber of digits exactly divisible by 7=" + c);

}

else

{

System.out.println("Entered number is negative");

while (n != 0)

{

int d = n % 10;

if (d % 5 == 0)

c+=d;

n/=10;

}

System.out.println("\nSum of digits exactly divisible by 5=" + c);

}

}

}

Variable Description:-

n:- Input variable to input a number

d:- Local variable to extract the digits

c:- To count the number of digits and to find the sum of digits

•Output attached

Answer 2

Question:

• Write a Java program using while loop to enter any integer and display how many digits in that number are perfectly divisible by 7 if the number is positive else find how many of the digits are divisible by 5 and the sum of those digits.

Program:

This is an easy question. Read this post to get your answer.

Here comes the program. (27 lines of code).

import java.util.*;

public class NumberOp

{

public static void main(String[] args)

{

int n, d, c=0, s=0, r;

Scanner sc=new Scanner(System.in);

System.out.print("Enter a number: ");

n=sc.nextInt();

d=(n<0)?5:7;

for(;n!=0;n/=10)

{

r=n%10;

if(r%d==0)

{

c++;

s+=r;

}

}

System.out.println((d==5)?"Negative.":"Positive.");

System.out.println("Number of digits divisible by "+d+" are "+c);

if(d==5)

System.out.println("Sum of digits is: "+s);

sc.close();

}

}

Logic:

Take a number as input, check if the number is negative or positive. According to the condition, divide the number by either 5 or 7. Count the number of digits divisible by the number 5 or 7. Store them in a variable. Find the sum of those number divisible by 5 and store them in another variable. Now, display the result.

Output is attached.