Find Biggest of Three Numbers in PHP

What You’ll Learn

Finding the biggest of three numbers is a classic conditional warm-up. This tutorial covers the comparison rule, a live preview, algorithm steps, worked PHP examples, edge cases, and complexity.

📝 Problem & Approach

Given three numbers a, b, and c, return the maximum among them.

# Example: a=14, b=7, c=22
# 22 >= 14 and 22 >= 7  → biggest is 22

Inputs & Outputs

Minimal workflow

function findBiggest(a, b, c):
    if a >= b and a >= c:
        return a
    if b >= a and b >= c:
        return b
    return c

Method comparison

🔮 Live Preview

Enter three numbers and check the biggest value instantly.

Press "Run" to see the biggest value.

Examples Gallery

Three complete PHP programs — if-elseif ladder, built-in max, and nested max. Click View Output to reveal sample console results.

<?php
function findBiggest(int $a, int $b, int $c): int
{
    if ($a >= $b && $a >= $c) return $a;
    if ($b >= $a && $b >= $c) return $b;
    return $c;
}

$a = 14; $b = 7; $c = 22;
echo "The biggest number is: " . findBiggest($a, $b, $c);
?>

The biggest number is: 22

<?php
function findBiggestWithMax(int $a, int $b, int $c): int
{
    return max($a, $b, $c);
}

$a = 14; $b = 7; $c = 22;
echo "The biggest number is: " . findBiggestWithMax($a, $b, $c);
?>

The biggest number is: 22

<?php
function max2(int $x, int $y): int
{
    return ($x > $y) ? $x : $y;
}

function findBiggest3(int $a, int $b, int $c): int
{
    return max2(max2($a, $b), $c);
}

echo findBiggest3(5, 5, 3) . PHP_EOL;
echo findBiggest3(-1, -4, -2) . PHP_EOL;
?>

5
-1

🔎 Worked Walkthrough — 14, 7, 22

Trace the if-elseif ladder with a = 14, b = 7, c = 22.

Tie example: for 5, 5, 3, the first branch 5 >= 5 and 5 >= 3 is true, so the answer is 5.

⚖️ Facts Worth Knowing

Handy follow-ups interviewers sometimes ask.

🎯 Practice Problems

Try these variations to lock in the pattern.

Notes

⏱️ Time and Space Complexity

💡 Best Practices