The question of obtaining prime numbers with a function

Gets the prime function between 100?200, main () {for ($i =100; $i <201; $i + +) {$b = False;for ($j =2; $j < $i-1; $j + +) {$k = $i% $j; if ($k = = 0) {$b = True;//break;}} if (! $b) {echo $i. "
";}}} My doubts at break that place, test the final result, there is no break, are the same result. But if you're going to use a program to explain a mathematical definition, you have to add a break, right?

Reply to discussion (solution)

No break will affect the printed result, because the printing condition is $i prime number
However, for operational efficiency, there is no break when you need to compare all the data ($i-1) before the end, and when there is a break when the first composite is found, then the invalid labor will not have to do

No break will affect the printed result, because the printing condition is $i prime number
However, for operational efficiency, there is no break when you need to compare all the data ($i-1) before the end, and when there is a break when the first composite is found, then the invalid labor will not have to do
+1

When you try to find a prime number within 20000 or greater, you know the difference between break and no break, you might as well test

......
Thanks to xuzuning, I have consolidated a basic knowledge.

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