PHP · Theory

md5()

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Theory

208/352

md5()

If you can teach md5() using Zara walking through md5, you know it. If you only know the heading, you don’t.

Keep md5() small. Zara should finish Zara walking through md5 in a few lines, not a 40-line dump.

md5() exists so Zara can keep Zara walking through md5 correct in a campus project.

Zara ships md5() in a campus project. That is the use case worth saying.

md5() trap — copy-pasting md5 without a dry-run. Zara loses marks for that every viva.

After md5(), Zara should still remember copy-pasting md5 without a dry-run.

Close md5() with — “If I skip it, Zara walking through md5 goes wrong like this: copy-pasting md5 without a dry-run.”

Exam tip

For md5(): definition + a campus project + one failure.

Example

<?php
// md5()
$scores = [80, 90, 70];
$avg = array_sum($scores) / count($scores);
echo "avg=" . number_format($avg, 1) . "\n";
foreach ($scores as $s) {
  if ($s >= 80) echo "high: $s\n";
}

md5(): scores array, print avg, then high marks. Say the output.

Short notes

Defmd5() — Zara uses it for Zara walking through md5 in a campus project.
Rulemd5() → one md5 step Zara can write from memory.
Remembermd5() + the PHP runtime (a campus project).
Usemd5() in a campus project (Zara walking through md5).
Trapmd5() — copy-pasting md5 without a dry-run.
Exmd5() → Zara walking through md5.

PHP · Theory

md5()

← All stacks

Theory

208/352

md5()

If you can teach md5() using Zara walking through md5, you know it. If you only know the heading, you don’t.

Keep md5() small. Zara should finish Zara walking through md5 in a few lines, not a 40-line dump.

md5() exists so Zara can keep Zara walking through md5 correct in a campus project.

Zara ships md5() in a campus project. That is the use case worth saying.

md5() trap — copy-pasting md5 without a dry-run. Zara loses marks for that every viva.

After md5(), Zara should still remember copy-pasting md5 without a dry-run.

Close md5() with — “If I skip it, Zara walking through md5 goes wrong like this: copy-pasting md5 without a dry-run.”

Exam tip

For md5(): definition + a campus project + one failure.

Example

<?php
// md5()
$scores = [80, 90, 70];
$avg = array_sum($scores) / count($scores);
echo "avg=" . number_format($avg, 1) . "\n";
foreach ($scores as $s) {
  if ($s >= 80) echo "high: $s\n";
}

md5(): scores array, print avg, then high marks. Say the output.

Short notes

Defmd5() — Zara uses it for Zara walking through md5 in a campus project.
Rulemd5() → one md5 step Zara can write from memory.
Remembermd5() + the PHP runtime (a campus project).
Usemd5() in a campus project (Zara walking through md5).
Trapmd5() — copy-pasting md5 without a dry-run.
Exmd5() → Zara walking through md5.

md5()

Example

Short notes

Questions

md5()

Example

Short notes

Questions