For Loop do action every 5 results

Question

can someone tell me the logic (in any language ) including pseudo code. on how to create a for loop an have it fire an action every 5 results it spits out.

basically I'm just trying to emulate a table with 5 columns.

Thanks!

Answer 1

you could use the modulus operator

for(int i = 0; i < 500; i++)
{
    if(i % 5 == 0)
    {
        //do your stuff here
    }
}

Answer 2

It's possible to use a condition with a modulus, as pointed out. You can also do it with nesting loops.

int n = 500;
int i = 0;

int limit = n - 5
(while i < limit)
{
   int innerLimit = i + 5
   while(i < innerLimit)
   {
       //loop body
       ++i;
   }
   //Fire an action
}

This works well if n is guaranteed to be a multiple of 5, or if you don't care about firing an extra event at the end. Otherwise you have to add this to the end, and it makes it less pretty.

//If n is not guaranteed to be a multiple of 5.
while(i < n)
{
  //loop body
  ++i;
}

and change int limit = n - 5 to int limit = n - 5 - (n % 5)

Answer 3

For an HTML table, try this.

<?php
$start = 0;
$end = 22;
$split = 5;
?>
<table>
    <tr>
  <?php for($i = $start; $i < $end; $i++) { ?>
    <td style="border:1px solid red;" >
         <?= $i; ?>
    </td>
    <?php if(($i) % ($split) == $split-1){ ?>
    </tr><tr>
    <?php }} ?>
    </tr>
</table>

Answer 4

for (int i = 0; i < 22; i++)
{
    if(i % 5 == 4)
    {
        // this happens every 5th time through the loop
    }
}

Answer 5

Another variation:

int j=0;
for(int i = 0; i < 500; i++) 
{ 
    j++;
    if(j >= 5) 
    { 
        j = 0;
        //do your stuff here 
    } 
}

I'm old fashioned, I remember when division took a long time. With modern cpus it probably doesn't matter much.