Instructions
Write a program that prompts the user to input a positive integer. It should then output a message indicating whether the number is a prime number. (Note: An even number is prime if it is 2. An odd integer is prime if it is not divisible by any odd integer less than or equal to the square root of the number.)

Answers

Answer 1

Answer: The c++ program to determine if the input number is prime is given below.

#include<iostream>

#include<math.h>

using namespace std;

int main() {

   int num, n;

   int prime=0;

   int i=3;

   cout<<"This program determines whether the number is prime." <<endl;

   do

   {

       cout<<"Enter any positive number."<<endl;

       cin>>num;

       if(num<=0)

           cout<<"Invalid input. Enter any positive number."<<endl;

   }while(num<=0);

   n=sqrt(num);

   if((num==1)||(num==2))

   {

       cout<<"The input "<<num<<" is prime."<<endl;

   }

   else if(num%2==0)

   {

       cout<<"The input "<<num<<" is not prime."<<endl;

   }

   else

   {

       do

       {

           if(num%i == 0)

               prime += 1;

           

           i++;

       }while(i<n);

        if(prime>1)

           cout<<"The input "<<num<<" is not prime."<<endl;

        else  

           cout<<"The input "<<num<<" is prime."<<endl;

   }

   return 0;

}

OUTPUT

This program determines whether the number is prime.

Enter any positive number.

-9

Invalid input. Enter any positive number.

Enter any positive number.

0

Invalid input. Enter any positive number.

Enter any positive number.

47

The input 47 is prime.

Explanation: This program accepts numbers beginning from 1. Any number less than 1 is considered as invalid input.

The test for prime is done using multiple if-else statements.

If number is even, it is not prime. Any number divisible by 2 is an even number. Except 2, it is even but also prime since it is divisible by itself only.

For odd numbers, number is divided by all odd numbers beginning from 3 till square root of the input. We first calculate and store square root of input.

n=sqrt(num);

An integer variable prime is initialized to 0. This variable is incremented each time the number is divisible by other number.

   int prime=0;

do

       {

           if(num%i == 0)

               prime += 1;            

           i++;

       }while(i<n);

Since prime number is only divisible by itself, all the prime numbers undergo this condition and hence, value of prime variable becomes 1.

The 0 and 1 values of variable prime indicate prime number. Other greater values indicate input is not prime.

if(prime>1)

           cout<<"The input "<<num<<" is not prime."<<endl;

        else  

           cout<<"The input "<<num<<" is prime."<<endl;

Answer 2

Python program checks if a positive integer is prime; uses a separate function to perform the primality test.

Here's a Python program that prompts the user to input a positive integer and then outputs a message indicating whether the number is a prime number:

```python

import math

def is_prime(n):

   if n <= 1:

       return False

   if n == 2:

       return True

   if n % 2 == 0:

       return False

   max_divisor = math.isqrt(n)

   for i in range(3, max_divisor + 1, 2):

       if n % i == 0:

           return False

   return True

def main():

   num = int(input("Enter a positive integer: "))

   if is_prime(num):

       print(f"{num} is a prime number.")

   else:

       print(f"{num} is not a prime number.")

if __name__ == "__main__":

   main()

```

Explanation:

1. The `is_prime` function checks whether the given number `n` is a prime number.

2. It first checks if the number is less than or equal to 1, in which case it returns False.

3. It then handles the case for the number 2 separately, as it is a prime number.

4. For odd numbers greater than 2, it iterates through odd divisors up to the square root of the number to check for divisibility.

5. If the number is divisible by any of these odd divisors, it returns False; otherwise, it returns True.

6. In the `main` function, the user is prompted to input a positive integer, and the result of the `is_prime` function is printed accordingly.


Related Questions

What are .Classification for computer softwares?

Answers

Answer: Classification of computer software are:-

System softwareApplication software

Explanation:

System software-it is the type of software that takes input from other  device ans sources and then covert it into machine language that is understood by the operating software.E.g.-UNIX Application software- it is the software that is connected with the end user through application present on the operating system which is accessed directly by the user. E.g.-Internet Explorer

Which of the following electronic payments is ideal for micropayments?

A. purchasing cards

B. smart cards

C. none of the methods listed

D. electronic checks

Answers

Smart cards are ideal for micropayments.

Write difference in the form of a table between Ping and TraceRoute command?

Answers

Explanation:

Ping

A network utility which is mainly used to test the connection between two devices or nodes. Ping is used to test the connectivity of a network and its name resolution.Syntax: ping <ip address>

TraceRoute

A network utility which is mainly used to track the path followed by a packet within a network from the source to the destination.It helps to trace the exact pathway of the data packet from the source to the destination.Syntax: tracert <ip address>

 

 

what is Interrupt?and give me information about Interruptstypes and processes and works?

Answers

Answer:

Interrupt is defined as, in computer system interrupts are the signal sent to the central processing unit by the external devices. The main function of interrupt is that, an operating system that provide multiprocessing and multitasking. The interrupt is a signal that causes the operating system to stop work on one processor and started work on another processor.

There are basically two type of interrupts:

Hardware interrupts - For the processor, if the signal is from external device and hardware is called hardware interrupts.Software interrupts - The interrupt which is caused by the software instructions are called software interrupt.

True / False
Some versions of the Von Neumann model include the stored program concept, but not all of them.

Answers

Answer: True

Explanation:

The Von Neumann model is based on the concept of stored program where both of the program and instruction data are stored in the same electronic memory. Though it is still used in many models but due to the Von Neumann bottleneck we have the introduction of the secondary memory.

What is the role of a Chief Information Officier in anorganization?

Answers

Answer and Explanation:

There are several roles of a Chief Information Officer in any organization and these are as follows:

He must fulfill his responsibility as a business leader.He must be able to make executive decisions regarding sales and purchase related matters. He must be able to deal with all the Information Technology related problems.He must be able to recruit the best candidates in the best interest of the organization.He is required to map out the ICT policy(includes procurement, external and internal standards of an organization, future proofing) and ICT strategy.He must be able to write up ICT policy  with detail of its utilization and application.He must possess organizational skills

What is one property of a good hash code?

Answers

Answer:- Major property of a good hash code is that objects which are equal should return the same hash code .

Explanation: Hash codes is a numeric value which  is used for identify a object while a equality testing .Hash code can occupy the value of any length and then returns a fixed length value. The value of hash codes are variable.

If two objects are equal then by the method of equal(object) if the hashcode() function is called on both the objects , they produce the same value.

If a CPU receives theinstruction to multiply the byte-sized values $12 and $3E, thisaction will take place in the ______________ (part of internal CPUhardware) section of the CPU.

Answers

Answer: Arithmetic and logic unit(ALU)

Explanation:  In central processing unit (CPU) , there are two main units CU(control unit) and ALU (arithmetic and logic unit) . ALU is responsible for any sort arithmetic and logical operation in the processor.This unit can perform mathematical operation like addition , multiplication divide , logical and many more. So the given operation of multiplication in the question will be done bu ALU of the CPU.

What are the advantages and disadvantage of integers and floating numbers?

Answers

Answer:

Explanation:

Advantages of int and disadvantages of float are as following :-

1.Arithmetic operation on int variables are much faster than float variables.

2.int variables does not suffer from precision loss while float variable sometimes suffer from it.

Advantages of float variables and disadvantages of int variables are as following:

1.float variables can represent values between integers.While integers cannot do that.

2.Float can represent much greater range of values than integers.

What is the output after the following code executes?

int x=10; if ( ++x > 10 ) {

x = 13;

}

cout << x;

Answers

Answer:

13

Explanation:

First understand the meaning of ++x, it is a pre-increment operator.

it means, it increase the value first than assign to the variable.

For example:

x=10

then after executing  ++x, the value of x is 11.

it increase the value and assign to x.

In the question:

The value of x is 10. After that, program moves to the if condition and check for condition (++x > 10) means (11 > 10) condition true.

then, 13 assign to x.

After that value of x is printed as 13.

Final answer:

The C++ code increments the variable x to 11 due to the pre-increment in the if statement, then changes x to 13 within the if block. Thus, the output of the code, when executed, is 13.

Explanation:

When the C++ code provided is executed, the statement int x=10; initializes the variable x with the value 10. The subsequent if statement checks if ++x > 10, where ++x is a pre-increment operation that increases x by 1 before the comparison. Since x is incremented to 11 before the comparison, the if block is executed, setting x to 13. The cout << x; statement then outputs the value of x, which at this point will be 13.

The characters << indicate that the value to the right is to be sent to the cout, which identifies the standard output stream. For cout to work, we need the inclusion of the iostream header file and the usage of the using namespace std; directive.

Write a program that prompts the user to enter the number of students and each student's name and score, and finally displays the student with the highest score and the student with the second highest score.

Answers

Answer:

  see attachment

Explanation:

You have not specified the language, or the details of the I/O form or prompts. Here is a program that does that, written in Wolfram language (the language of Mathematica).

It prompts separately for student name and student score. The minimum score is presumed to be higher than -99999. If only one student name is entered, the second output is that score with no name listed. There is no error checking.

We have elected to keep a list only of the two two scores, and to sort that list again each time a new entry is made.

__

The attachment shows the output of the program below the program listing.

A database is called "self-describing" because it contains a description of itself.

A.

True

B.

False

Answers

Answer:

true

Explanation:

Which keyboard shortcut is typically used to move to the previous entry box?

A. Ctrl+Enter
B. Tab
C. Enter
D. Ctrl+Tab

Answers

Answer:

D. Ctrl+Tab

Explanation:

The Ctrl+Tab shortcut is typically used to move to the previous entry box.

.The operation signature has all the following except:
A.name of the operation B.object accepts C.algorithm ituses D.value returned by the operation

Answers

Answer: C) algorithm it uses

Explanation: The operation signature has the name of operation ,objects that it accepts and the value returned by the operation but it does not have algorithm that it uses.As algorithm defines all the steps that are to be used to find the result so signature operation does not include the whole algorithm that is to be used. The signature operation verifies the steps of the algorithm in way.

. Frequency band in which 99% of the total power resides iscalled _________

a. Power bandwidth

b. half power bandwidth

c. 3dB bandwidth

d. 4dB bandwidth

Answers

Answer:

Frequency band in which 99% of the total power resides iscalled Power bandwidth-a.

Data mining must usestatistics to analyze data.
True
False

Answers

Answer: True

Explanation: In data mining, they use statistics component for the analyzing of the large amount of data and helps to deal with it. Statistics provide the techniques for the analyzing, evaluating and dealing with the data that is known as data mining.Data statistics provide the help to organize large data in a proper form and then analyze it. Thus, the statement given is true that data mining must use statistics to analyse data.

One lap around a standard high-school running track is exactly 0.25 miles. Write a program that takes a number of miles as input, and outputs the number of laps. Output each floating-point value with two digits after the decimal point, which can be achieved as follows: System.out.printf("%.2f", yourValue); Ex: If the input is:

Answers

Answer:

import java.util.Scanner;

public class Miles {

public static void main(String[] args) {

   //initialization

       double Number_Miles;

       //print the message

       System.out.print("Enter the number of miles: ");

       Scanner scn1 = new Scanner(System.in);

       

       Number_Miles = scn1.nextDouble();  //read the input from user

       //calculate the laps

       double yourValue = Number_Miles/0.25;

       //display the output on the screen

       System.out.printf("%.2f", yourValue);

     

}

}  

Explanation:

First import the library Scanner than create the class and define the main function. In the main function, declare the variables.

print the message on the screen and then store the value enter by the user into the variable.

Scanner is a class that is used for reading the output. So, we make the object of the class Scanner and then object call the function nextDouble() which reads the input and store in the variable.

After that, calculate the number of laps by dividing the number of miles with the given one lap running track value (0.25 miles).

[tex]Number\,of\,laps = \frac{Number\,of\,miles}{0.25}[/tex]

the output is stored in the variable.

After that, print the value on the screen with 2 digits after the decimal point.

we can use "%.2f" in the printing function in java.

like System.out.printf("%.2f", output);

Answer:

def miles_to_laps(miles):

  return miles / 0.25

miles = 5.2

num_of_lap = miles_to_laps(miles)

print("Number of laps for %0.2f miles is %0.2f lap(s)" % (miles, num_of_lap))

Explanation:

What is the advantages and disadvantagesof International Standards for NetworkProtocols.

Answers

Answer:

Advantages and disadvantages of international standards for network protocols are:

Advantages -

Due to common underlying standard maintenance and installation become easy. Many computers can connect together from all the worldwide, as they are using the international standard for network protocol. One of the main advantage using international standard as it boost up growth and economy.

Disadvantages -

Every network standard has its own limitations in a particular domain. Once it is spread worldwide then it is difficult to resolve network issues.

Decision trees are best suitedfor:
one decision inone period.
one decision overseveral periods.
several decisionsover one period.
several decisionsover several periods.
None ofthese.

Answers

Answer: Decision Trees are best suited for several decisions over one period.

Explanation:

Decision tree gives an effective method for making decisions. It is a tree-like model used for decisions and analyses consequences, including resources cost, outcome and utility. It also helps us to make best and good quality decisions on the basis of given information. It is also widely used in machine learning and commonly used  in data mining as a tool.

Explain the purpose (using only two sentence in each case) of eachof the following
components of UML

• Use case diagram
• Use case description
• Class diagram
• Sequence diagram
• Business or Domain model

Answers

Answer:

UML - Unified Model Language

Explanation:

Use case diagram:

A use case diagram is used to tell how many ways a   user can interact with  a system. We use special   symbols and connectors to build use case   diagrams.  

We use  horizontal shaped ovals to represent use   cases, stick figures to represent actors, lines to   represent associations between use cases and  

actors, packages to put elements into  groups.  

Use case description:  

By the name itself, we can say that it is used to   describe the activities of user that  he can do with   the system and how the system responds to those.  Before use case diagram created, we need to write   a use case description.  

Class diagram:  

UML diagrams are of two types. They are,  

Structural UML diagrams Behavioral UML diagrams

A class diagram comes under Structural UML   diagrams.

Classes are building blocks of an application that   uses OOPs concepts. Class diagrams are used to   represent classes, relationships, association,  

interface.  

Sequence diagram:  

A sequence diagram comes under  Behavioral UML   diagrams.It is used to tell the sequential order of   objects' interaction.We have many notations in this   diagram like actors, lifeline, create message, delete   message, lost message, found message etc. It is   used to tell how messages move between objects in   a system.  

Domain model :  

A domain model is a visual representation of real-  situation objects. In UML,  the Domain Model is   illustrated with a set of class diagrams

What is the height of the tallest possible red-black tree containing 31 values?

Answers

Answer:

The height of tallest possible red-black tree having 31 values is 10.

Explanation:

The height of tallest possible red-black tree = 2㏒₂(n+1)

here we have n=31 So substituting the value of n in the equation.

=2㏒₂(31+1)

=2㏒₂(32)

=2㏒₂(2⁵)                   since ㏒(aⁿ)=n㏒(a)  

=2x5㏒₂(2)

=10㏒₂(2)                   since ㏒ₙ(n)=1.

=10.

Write a program which prompts user to enter a character, if the user presses „Z‟, the program asks user to enter a number. In this case the program implements 5-input majority voting logic which is explained as follows.The value of the number represented by the five leftmost bits of Register-B is tested. If the number of logic '1' bits (in the 5 leftmost bits) is greater than the number of logic '0' bits, the program should output: "The number of 1’s in the 5 left most bits is greater than the number of 0’s". If the number of logic '0' bits (in the 5 leftmost bits) is greater than the number of logic '1' bits, the program should output: "The number of 0’s in the 5 left most bits is greater than the number of 1’s"

Answers

I’m pretty sure the answer is A

FS and GS are two___________________ in protected mode.
? segment registers
? segment selectors
? stack pointers
? register pointers

Answers

Answer:

Segment registers

Explanation:

The initial purpose behind the segment registers was to enable a program to access many distinct (big) memory sections designed to be autonomous and part of a constant virtual store.

They don't have a processor-defined objective, but instead Operating system runs them for purpose. The GS register is used in Windows 64-bit to point to constructions defined by the operating scheme.   Operating system kernels usually use FS and GS to access thread-specific memory. In windows, thread-specific memory is managed using the GS register. To access cpu-specific memory, the linux kernel utilizes GS.

In ________ for final fields and methods the value is assignedlater but in ______ you assign the value during declaration.
Java , C++
C++ , C#
Java , C#
C++ ,Java

Answers

Answer:

The answer to this question is Java,C++.

Explanation:

We can assign non static final variables a value with the declaration or in the constructor but this is not the case with c++ because we have to assign value during declaration and c++ equivalent of final is const keyword and there is sealed or readonly keywords in c# not final.If we do not assign value at the time of declaration the const variable will contain garbage value which cannot be changed afterwards.

Answer:

The answer to this question is Java,C++.

Explanation:

We can assign non static final variables a value with the declaration or in the constructor but this is not the case with c++ because we have to assign value during declaration and c++ equivalent of final is const keyword and there is sealed or readonly keywords in c# not final.If we do not assign value at the time of declaration the const variable will contain garbage value which cannot be changed afterwards.

Give brief comparison of Broadcast, Unicastand Multicast?

Answers

Answer:

In broadcast the message is transmitted from one to all , in uni cast we have one to one transmission and in multicast we have transmission from one to many.

Explanation:

If we take the example of a simple messaging application it will be clear. If a message is exchanged between one person to another, then it is uni casting. If a person sends a message to all the persons in his contact list then it is broadcasting and  if a person sends messages to select persons in his contact list then it is multi casting. In multi casting management of the group is required regarding who can receive messages which is not required in broadcasting.

Class objects cannot be passed as parameters to functions or returned as function values.

True

False

Answers

I think true but I am not sure

Final answer:

The statement is false; class objects can indeed be passed as parameters to functions and returned as function values in many object-oriented programming languages.

Explanation:

The statement that class objects cannot be passed as parameters to functions or returned as function values is false. In many programming languages, especially those that support Object-Oriented Programming (OOP), it is common to pass objects as arguments to functions or methods, and also to return them as function values. This is part of the encapsulation feature in OOP, where an object bundles data and methods that operate on that data, allowing the methods direct access to the object's data without necessarily passing them as individual parameters.

For example, consider a Python class named Book. You can create an instance of this class and pass it to a function:

def display_book_info(book):
   print(book.title)
   print(book.author)

my_book = Book("Pride and Prejudice", "Jane Austen")
display_book_info(my_book)

In this case, my_book, which is an object of the class Book, is being passed as a parameter to the function display_book_info.

Programs that are embedded in a Web page are called Java ____.

a.
consoles

b.
windowed applications

c.
applications

d.
applets

1 points

Answers

Answer:

applets

Explanation:

Java applets are dynamic programs that can be embedded on a webpage and run on a web browser like internet explorer,firefox or google chrome. The code for applets is developed using java programming language and facilitates interesting and complex display entities to be included as part of the web page. HTML provides a special tag called <Applet> for providing details of the applet.

When you declare a method as abstract method ? Can I call a abstract method from a non abstract method ?

Answers

Answer: A method without body is called abstract method. A abstract method can be called from a non abstract  class or method provided it is inherited using a subclass.

Explanation:

An abstract method is a method which does not have a body, it just has opening and closing curly braces. A class having an abstract method is also declared as abstract class. We cannot make an object of the abstract class.

example : public abstract float multiply(float x, float y);

is an example of abstract method.

calling an abstract method from a non  abstract method is possible provided it is inherited by a non abstract subclass.

for a small to medium enterprise , the benefits of setting up an e-commerce store front include ( choose all that apply)

A. The ability to offer a larger selection of products

B. the ability to reach a wider customer base

C. the ability to eliminate advertising

D. the ability to offer lower prices to customers

Answers

Answer:

All of the above

Explanation:

The ability to reach a wider customer base, the ability to offer lower prices to customers, the ability to offer a larger selection of products and the ability to eliminate advertising. The correct options are A, B, C and D.

What is e-commerce store front?

An electric storefront is a web-based solution that allows business owners to advertise and sell goods and services over the internet.

This is a fundamental form of e-commerce in which the buyer and seller interact directly.

To enable merchants to sell their products online, it combines transaction processing, security, online payment, and information storage.

A storefront, also known as a shopfront, is the facade or entryway of a retail store on the ground floor or street level of a commercial building, typically with one or more display windows.

A storefront's purpose is to draw attention to a company and its products.

The makes it possible to reach a larger customer base, to offer lower prices to customers, to offer a larger selection of products, and to eliminate advertising.

Thus, all options are correct.

For more details regarding storefront, visit:

https://brainly.com/question/971394

#SPJ2

A ____________________ can be used to hierarchically represent a classification for a given set of objects or documents. A. taxonomy B. framework C. scheme D. standard

Answers

Answer:

A. taxonomy

Explanation:

A taxonomy can be used to hierarchically represent a classification for a given set of objects or documents.

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Negative the quantity of the quantity 2 multiplied by b plus 8 end of quantity divided by the quantity 10 multiplied by b end of quantity end of quantity. how much is 2 plus 9 Using the Antoine equation, prepare two plots of Psat versus T for Benzene over the range of temperature for which the parameters are valid. One plot should present Psat on a linear scale and the other should present Psat on a log scale. Make these plots using appropriate software of your choice (Excel, Matlab, etc.), not by hand. In both cases, T should be on the horizontal axis (independent variable) and Psat nwww ww www. should be on the vertical axis. Please show all work and use Excel or Matlab. The parameters for Benzene are given below. A 13.7819 B 2726.81 C 217.572 Temp Range( C) 6-104 AHn (kJ/mol) 30.72 Latent heat of Vaporization at normal boiling point a0000nd Normal boiling point Tr (oC) 80.0 Find the values of k for which the quadratic equation 2x^2 (k + 2)x + k = 0 has real and equal roots. 9x^2 + 24x + 20 = 4Solve this by factoring.Thank you! Find the area of quadrilateral ABCD. [Hint: the diagonal divides the quadrilateral into two triangles.]A. 26.47 unitsB. 28.53 unitsC. 27.28 unitsD. 33.08 units In solid motors, HTPB and PBAN are two common types of plasticizers. a) True b) False You are given the dollar value of a product in 2015 and the rate at which the value of the product is expected to change during the next 5 years. Write a linear equation that gives the dollar value V of the product in terms of the year t. (Let t = 15 represent 2015.) Two cars leave Memphis from exactly the same spot at exactly the same time, one traveling north at an average speed of 70 mph and the other traveling south at an average speed of 65 mph. Approximately how long does it take before the cars are 270 miles apart? Which of the following increases the chance of a reaction when twomolecules collide?OA. Increasing the concentration of the moleculesOB. Increasing the activation energy of the reactionOC. Decreasing the temperature of the systemOD. Slowing down the speed of the molecules X-rays with an energy of 400 keV undergo Compton scattering with a target. If the scattered X-rays are detected at \theta = 30^{\circ}=30 relative to the incident X-rays, what is the energy of the recoiling electron?