Group and sum duplicate elements in a for loop - php

Question

I have a for loop like so:
for((int) $i = 0; $i < $number_of_updates; $i++)
{
//query here
$result = mysql_query($query);
list($name) = mysql_fetch_row($result);
$points = 1;
//some functions to execute here... and then
//store results in session to show on other page
$output = $points.' times '.$name;
$_SESSION['item'][] = $output;
}
And then I show my results on view page like so:
foreach (array_unique($_SESSION['item']) as $output)
{
echo ('<p>'.$output.'</p>');
}
It echoes my results out of the loop like so:
1 times foo
1 times foo
1 times bar
1 times foo
etc...
Now the question. How do I sum those results up so they don't duplicate? Instead they are shown like so:
3 times foo
1 times bar

Answer 1

User array_count_values
for(/*(int) <- this is not neccessary (c++ background?) */ $i = 0; $i < $number_of_updates; $i++)
{
// your code
$_SESSION['item'][] = $name;
}
foreach(array_count_values($_SESSION['item']) as $name => $times)
echo ('<p>'.$times.' times '.$name.'</p>');
Of course counting the values directly is more memory and time efficient. This version is only neccessary if you somehow need to preserve the order of the elements.

Answer 2

Why didn't you store in your array directly the sum?
for((int) $i = 0; $i < $number_of_updates; $i++)
{
//query here
$result = mysql_query($query);
list($name) = mysql_fetch_row($result);
$points = 1;
//some functions to execute here... and then
//store results in session to show on other page
$_SESSION['item'][$name] +=$points;
}

Answer 3

Try this:
for((int) $i = 0; $i < $number_of_updates; $i++)
{
//query here
$result = mysql_query($query);
list($name) = mysql_fetch_row($result);
$points = 1;
//some functions to execute here... and then
//store results in session to show on other page
//$output = $points.' times '.$name;
//$_SESSION['item'][] = $output;
if( isset( $_SESSION['count'][$name] )){
$prev = $_SESSION['count'][$name];
}else{
$prev = 0;
}
$_SESSION['count'][$name] = $points + $prev ;
}
print_r( $_SESSION['count'] );