CODEWITHSUNDEEP
phpstrstr
user4298677
user4298677

Reputation:

Why don't I get the same output?

I am trying to check whether a string is PANGRAM but both the codes give different results.

Number One - 

<?php
$line = strtolower(trim("thequickbrownfoxjumpsoverthelazydog"));
$letters = str_split("thequickbrownfoxjumpsoverthelazydog");
$result = "pangram";

foreach ($letters as $value) {
    if (strstr($line, $value) == FALSE) {
        $result = "not pangram";
    }
}
echo $result;
?>

Number Two -

<?php
$line = strtolower(trim("thequickbrownfoxjumpsoverthelazydog"));
$letters = str_split("thequickbrownfoxjumpsoverthelazydog");
$result = "not pangram";
foreach ($letters as $value) {
    if (strstr($line, $value) == TRUE) {
        $result = "pangram";
    }
}

echo $result;
?>

Upvotes: 2

Views: 297

Answers (3)

Ishak Ali
Ishak Ali

Reputation: 350

very simple panagram checking code 

$string = "The quick brown fox jumps over the lazy dog";
$stringData = str_split(strtolower($string));
$check = range('a', 'z');
$res = array_intersect($check, $stringData);
if(count($check) === count($res)) echo 'panagram';
else echo 'not panagram';

thats it

Upvotes: 2

Barmar
Barmar

Reputation: 780889

The second version is incorrect because you can't determine that a sentence is a pangram based on checking just one character from the alphabet. So finding a matching character doesn't mean that it's a pangram. The only thing you can do is determine that a sentence is not a pangram when one of the letters in the alphabet does not exist in the test string. So you have to start with the assumption that it's a pangram, search for each letter, and when a search fails you conclude that it's not.

You can also stop looping once that happens -- one failure is enough to conclude that it's not a pangram.

foreach ($letters as $letter) {
    if (!strstr($line, $letter)) {
        $result = "not pangram";
        break;
    }
}

Upvotes: 0

taxicala
taxicala

Reputation: 21759

You have to use predicates, otherwise the result might change on each tick of the iteration:

$line = strtolower(trim("thequickbrownfoxjumpsoverthelazydog"));
$letters = str_split("thequickbrownfoxjumpsoverthelazydog");
$result = true;
foreach ($letters as $value) {
    $result = $result && strstr($line, $value);
}

echo $result ? "pangram" : "not pangram";

With your code, if the first letter is found, the result will be TRUE, but if the next is not found, it will be FALSE, and, if the third is found, it will be TRUE again, and so on...

Upvotes: 0

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