php loop and control flow - php

Question

i am having problems in exploding array and working with it.
i have array of serial numbers for books categorized as read and unread books.
when ever there is book that is read i place read in array after that serial number as follow.
array(
"1234567890","read",
"2345678901","read",
"2345678901",
"2345678901",
"1234561231",
"3333333333","read",
"3333333333"
)
status is unread for all others and in out put i want to loop through the array give me this result.
1234567890: 0 unread, 1 read
2345678901: 2 unread, 1 read
1234561231: 1 unread, 0 read
3333333333: 1 unread, 1 read
any help will be appreciated .

Answer 1

In the first time that array you have is not build in the best way, better would be :
$arr = array(
"1234567890","read",
"2345678901","read",
"2345678901","unread"
)
but you can do this:
$idx=count($arr);
$collector=array();
for($i=0;$i<$idx;$i++){
if($arr[$i]==='read') continue;
if(!isset($collector[$arr[$i]])){
$collector[$arr[$i]]=array(0,0);#array(read,unread)
}
if($arr[$i+1]==='read'){
$collector[$arr[$i]][0]++;
} else {
$collector[$arr[$i]][1]++;
}
}
#print it
foreach($collector as $id => $data){
print "$id: {$data[0]} read , {$data[1]} unread<br>".PHP_EOL;
}
But better try to collect the data in a better way!!!

Answer 2

Use Multidimensional array instead:
<?php
$arrBooks = array(
"1234567890" => array(
"read"=>'1',
"unread"=>'0'),
);
foreach ($arrBooks as $obj_key =>$book)
{
echo "$obj_key:<br>";
foreach ($book as $key=>$value){
echo "$key: $value<br>";
}
echo "<br>";
}
This way you can easily loop through the keys and get the data accordingly.
If you wish to update the arrays as well, here is the piece of code:
foreach ($arrBooks as $obj_key =>$book)
{
if($obj_key=="1234567890")
{
foreach ($book as $key=>$value){
if($key=="read")
{
$value+=1;
}
echo "$key: $value<br>";
}
}
}