Write a C/C++ program to generate prime number list and check whether a number is prime or not

Question

0.00/5 (No votes)

See more:

I can write the code for "Sieve of Eratosthenes" to generate all the prime number up to n. But I want to write a program that will generate and index all the prime number (up to n) into an array, than check whether a number is prime or not. Can anyone please help me to do it?

For Example: if n = 10, than the prime number is 2 3 5 7. Index them into an array a[ ] = {2, 3, 4, 7}. Than write a program and press a number as input from keyboard, than check the number is prime or not. I know that there is a simple way to check whether a number is prime or not but I want to do it by the above way. How can I do that???

Posted 9-Nov-12 1:44am

Ihteshamul Alam

Updated 9-Nov-12 1:46am

v3

Add a Solution

1 solution

Add a Solution

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

Richard MacCutchan · Answer 1 · 2012-11-09T02:22:00

Since you mark all numbers in your original code as prime or not, you should already have a lookup table which you can use.

Alternatively you could create an array or use a simple vector[^] or list[^] to store them. Then when the user enters a value you can look it up in the container and report accordingly.

Sieve of Eratosthenes in C#[^] is a sample article that should help.