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  Generate first N prime numbers

Recently I am taking an online course named "Startup Engineering" on coursera. There is one assignment which is to use NodeJS to write a program to generate the first 100 prime numbers. This may be very easy for many people. Here I just want to share with you the code to generate not only the first 100 prime numbers. but also any number of prime numbers.Below is the code snippet://Helper class to generate prime numbersvar PrimeProcessor=(function(){ var primeArray=[]; function _isPrime(num){ if(num<=1){ throw new Error("Number cannot be sm...

11,757 5       JAVASCRIPT ALGORITHM NODEJS PRIME NUMBER COURSERA


  A Perl Regular Expression That Matches Prime Numbers

perl -lne '(1x$_) =~ /^1?$|^(11+?)\1+$/ || print "$_ is prime"'Can you figure out how it works? I give an explanation below, but try to figure it out yourself. Here is what happens when you run it:$ perl -lne '(1x$_) =~ /^1?$|^(11+?)\1+$/ || print "$_ is prime"'122 is prime33 is prime455 is prime677 is prime89101111 is primeHere is how it works.First, the number is converted in its unary representation by (1x$_). For example, the number 5 gets converted into 1x5, which is 11111 (1 repeated 5 times.)Next, the unary string gets tested against the regular expression. If it matches, the number is ...

5,289 0       REGULAR EXPRESSION PERL REGEX PRIME NUMBER ONE LINE