Finding how many digits does every number has in an array in php

Question

I have an array which has several numbers. What I want to do is get a loop and run into this array and count how many two-digits numbers, three-digits, four-digits numbers do I have.

What I have tried:

$myArray = array(123,1234,12345,123456,123567);
for($i=1,$size=count($myArray);$i<=$size;i++)
{
if(strlen($i==3)) echo "the number with index " .$i. " is three-digit number.";
else if(strlen($i==4)) echo "the number with index " .$i. " is four-digit number.";
...
}

I also tried this:

$threeDigits=0;
$fourDigits=0;
$fiveDigits=0;
$sixDigits=0;

$myArray=(123,1234,12345,123456,1234567,111,222)
for($i=1,$size=count($myArray);$i<=$size;i++)
{
if(strlen($==3)) $threeDigits++;
else if(strlen($i==4)) $fourDigits++;
else if(strlen($i==5)) $fiveDigits++;
else if(strlen($i==6)) $sixDigits++;
}
echo "There are " .$fourDigits. " numbers with 4 digits.";
echo "There are " .$threeDigits. " numbers with 3 digits.";
echo "There are " .$fiveDigits. " numbers with 5 digits.";
echo "There are " .$sixDigits. " numbers with 6 digits.";

But somehow it only reads them as one. As you can see, in my array there are three three-digit numbers but when I print it out it says I have only one. What do you think it might be the problem here?

I'm not sure of the metrics involved but perhaps sort the array first? — Professor Abronsius, Sep 14 '21 at 21:55
Define "best"...what are you unhappy about in the current solution? It's hard to suggest an improvement unless you can describe a problem and/or a more specific goal — ADyson, Sep 14 '21 at 22:27
Hint: iterating over array is simplier with `foreach` -> `foreach(myArray as key, value) ` or just `foreach(myArray as value)` — Marcin Orlowski, Sep 14 '21 at 22:32
Near dupe: https://stackoverflow.com/a/1762216/2943403; I'll try to find a better one — mickmackusa, Sep 14 '21 at 22:57
Related: https://stackoverflow.com/q/50145408/2943403 , https://stackoverflow.com/q/4598048/2943403 , https://stackoverflow.com/q/2309626/2943403 , https://stackoverflow.com/q/32430993/2943403 , https://stackoverflow.com/q/59785175/2943403 — mickmackusa, Sep 14 '21 at 23:15

score 0 · Answer 1 · answered Sep 14 '21 at 22:28

0

Just for the hell of it, map it as a callback:

foreach(array_map('strlen', $myArray) as $key => $len) {
    echo "the number with index $key is a $len digit number.";
}

answered Sep 14 '21 at 22:28

AbraCadaver

78,200
7
66
87

Hi, can you please take a look at my edited question? Maybe it will give you a clearer idea of what I want to achieve. I don't want the index of the two/three/four digit number, I want to count how many three/four/five-digit numbers I have. – Sep 15 '21 at 07:23

score -1 · Answer 2 · answered Sep 14 '21 at 22:34

Store the lengths in an array:

$myArray = array(123,1234,12345,123456,123567);
$lengths = [];
foreach ( $myArray as $val ) {
  $lengths[strlen($val)]++;
}

foreach (range(2,4) as $len)  {
  echo "There are " . $lengths[$len] . " $len-digit numbers\n";
}

Finding how many digits does every number has in an array in php

2 Answers2