How do I break a for-loop in PHP when conditions are met?

php loops primes
Alex Mcp picture Alex Mcp · Jun 28, 2009 · Viewed 50.8k times · Source

I'm diligently plugging away at some code that checks for divisibility (yes, it's to generate primes) and I want to know how to stop a for... loop if the condition is met once. Code like this:

$delete = array();
foreach ( $testarray as $v ) {
    for ( $b = 2; $b < $v; $b++ ) {
        if ( $v % $b == 0 ) {
            $delete []= $v;
        }
    }

So $testarray is integers 1-100, and the $delete array will be filtered against the $testarray. Currently though, a number like 12 is being added to $delete multiple times because it's divisible by 2, 3, 4, and 6. How can I save my computer's time by skipping ahead when the criteria matched once?

Answer

Sampson picture Sampson · Jun 28, 2009 
break; #breaks out of a loop
continue; #skips rest of current iteration

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