1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
umka21 [38]
3 years ago
8

Prime numbers can be generated by an algorithm known as the Sieve of Eratosthenes. The algorithm for this procedure is presented

here. Write a program called primes.js that implements this algorithm. Have the program find and display all the prime numbers up to n = 150.
Sieve of Eratosthenes Algorithm
To Display All Prime Numbers Between 1 and n
Step 1: We need to start with all the numbers representing the range of numbers that are possible candidate primes. So, create an array of consecutive integers from 2 to n: (2,3,4,..n). I wouldn't hand-code this. I would use a loop to populate the array.
Step 2: At each step we select the smallest number and remove all it's multiples. So we'll start with an outer loop that goes from 2 to n. initially, let p equal 2, the first prime number.
Step 3: In an inner loop we need to iterate over all the numbers that are multiples of p, i.e for 2, that's 2,4,6,8 etc. Each time, setting it's value to false in the original array.
Step 4: Find the first number greater than p in the list that is not marked False. If there was no such number, stop. Otherwise, let p now equal this number( which is the next prime), and repeat from step 3.
When the algorithm terminates, all the numbers in the list that are not marked False are prime
Example: Let us take an example when n = 50. So we need to print all print numbers smaller than or equal to 50. We create list of all numbers from 2 to 50.
2 3 4 5 6 7 8 9 10
11 12 13 14 15 16 17 18 19 20
21 22 23 24 25 26 27 28 29 30
31 32 33 34 35 36 37 38 39 40
41 42 43 44 45 46 47 48 49 50
Computers and Technology
1 answer:
Sidana [21]3 years ago
4 0

Answer:

const MAXNR=150;

let candidates = {};

for(let i=2; i<=MAXNR; i++) {

   candidates[i] = true;

}

for(let p=2; p <= MAXNR; p++) {

   if (candidates[p]) {

       process.stdout.write(`${p} `);

       // Now flag all multiples of p as false

       i=2;

       while(p*i <= MAXNR) {

           candidates[p*i] = false;

           i++;

       }

   }

}

You might be interested in
Write a program that asks the user to enter a number within the range of 1 through 10. Use a switch statement to display the Rom
Studentka2010 [4]

Answer:

// program in C++.

// headers

#include <bits/stdc++.h>

using namespace std;

// main function

int main()

{

// Variable

   int num;

   cout << "Enter a number between 1 and 10: ";

   // read input

   cin >> num;

   // validate input number

   while(num<1||num>10)

   {

   // if input is wrong then print error message

       cout<<"Wrong input!!Enter again:";

       // read again

       cin>>num;

   }

   // print output

   cout << "The Roman numeral for "<<num<<" is:";

   // switch

   switch (num)

   {

       case 1:

       // if input is 1

           cout<<"I"<<endl;

           // exit the switch

           break;

       case 2:

       // if input is 2

           cout<<"II"<<endl;

           // exit the switch

           break;

       case 3:

       // if input is 3

           cout<<"III"<<endl;

           // exit the switch

           break;

       case 4:

       // if input is 4

           cout<<"IV"<<endl;

           // exit the switch

           break;

       case 5:

       // if input is 5

           cout<<"V"<<endl;

           // exit the switch

           break;

       case 6:

       // if input is 6

           cout<<"VI"<<endl;

           // exit the switch

           break;

       case 7:

       // if input is 7

           cout<<"VII"<<endl;

           // exit the switch

           break;

       case 8:

       // if input is 8

           cout<<"VIII"<<endl;

           // exit the switch

           break;

       case 9:

       // if input is 9

           cout<<"IX"<<endl;

           // exit the switch

           break;

       case 10:

       // if input is 10

           cout<<"X"<<endl;

           // exit the switch

           break;

         // default

       default:

           break;

   }

return 0;

}

Explanation:

Read a number from usr and assign it to variable "num". If the input number is less than 1 or greater than 10 then ask again to enter a number until user  enter a number between 1-10 only.Then with the help of switch() function print  the equivalent Roman number.

Output:

Enter a number between 1 and 10: -5                                                                                        

Wrong input!!Enter again:12                                                                                                

Wrong input!!Enter again:6                                                                                                

The Roman numeral for 6 is:VI

7 0
3 years ago
Which element is the first thing you should complete when making a movie?
AlekseyPX

Answer:

storyboard!!!

Explanation:

its important to have the concept in mind before starting

6 0
3 years ago
Read 2 more answers
Write an if/else statement that adds 1 to the variable minors if the variable age is less than 18, adds 1 to the variable adults
Mama L [17]

Answer:

Explanation:

data is a statement like

data 10,20, 30 , 40 , 50, 60 , 70, 80

\\the numbers represent ages.

For x := 1 to end of data do a[x]:=read(data)

\\ This is a comment. You could do this much easier if you just use three if statements rather than the if then else.

minor:=0;adult:=0;senior:=0;

while a[x] <> 0 do begin

age:= a[x]

if age < 19 then minor:=minor + 1;

If age > 18 then if age < 65 the adult:=adult + 1;

if age > 64 then senior := senior + 1;

end;

I have not declared the variables anywhere. That depends on what language you are using. The key step you  want are the three if statements. How you find out what's in them is another matter.

6 0
3 years ago
A programmer has a need to round many numeric values to the nearest integer. Which of the following best explains the benefit of
12345 [234]

Answer:

Keeping the numeric values in a list makes it easier to apply the same computation to every data element.

Explanation:

A list or array in programming is a data structure, that has the location for each item it holds indexed. It eliminates the need to constantly create a variable to compute items of the same data types.

The list can store items of the same data type and iterate over them to compute the same calculation on each of them.

5 0
3 years ago
What is a file manager? Give an example.
Lelechka [254]

Answer:

A file manager is a type of manager where you manage your files. Thee are many types of functions in a file manager. You can compress certain types of files, you can move delete, etc your files. You can transfer or share certain types of files as well.

8 0
4 years ago
Other questions:
  • Describe a situation where it would be appropriate to use each of the six leadership styles described by Daniel Goleman
    7·1 answer
  • Hey im trying to get a refund because i got charged 24$ for the yearly plan and i didnt know i would get charged can i get the y
    11·1 answer
  • What should you keep in mind when typing a message on the Internet?use as many A.acronyms as it saves space
    7·1 answer
  • What is the name of the image window area that identifies the project you are working on?
    7·1 answer
  • Define and discuss statistical significance as it pertains to web analytics, formulate your own opinions of what this means. in
    8·1 answer
  • How do productivity programs most benefit the way we work and live?
    12·2 answers
  • Write a Python program stored in a file q1.py to play Rock-Paper-Scissors. In this game, two players count aloud to three, swing
    13·1 answer
  • When the function below is called with 1 dependent and $400 as grossPay, what value is returned?
    13·1 answer
  • What is the reason for taking care of design a good computer human interface ​
    9·2 answers
  • * Describe the five components of a<br> computer
    6·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!