How to identify if given number is there in a given array range?

Question

I have an array which stores numbers. The count of numbers varies time to time. There is another variable which a holds number, and I need to find out in which range $num falls. In the above case $num falls under 64. (Bigger than 32 and less than 64)

$ar = array(0, 32, 64, 96, 128, 160, 192, 224);

$num = 44;

How do I crack this?

First sort the array then find index of your number then one below and one above that are your answers — Hanky Panky
– Hanky Panky, Commented May 17, 2013 at 11:29
@ØHankyPankyØ, the array contains only the ranges, not the used number. — enenen
– enenen, Commented May 17, 2013 at 11:48

zerkms · Accepted Answer · 2013-05-17 11:32:12Z

7

$ar = array(0, 32, 64, 96, 128, 160, 192, 224);

$num = 44;

$range = min(array_filter($ar, function($i) use($num) {
    return $i > $num;
}));

var_dump($range);

Online demo: http://ideone.com/KV6MWD

answered May 17, 2013 at 11:32

zerkms

256k73 gold badges447 silver badges551 bronze badges

Sign up to request clarification or add additional context in comments.

6 Comments

alex Over a year ago

I like this Zmayte. If only there was a nice way to terminate array_filter() only.

SubSevn Over a year ago

With a sorted array, you can also do this in O(log n) time, instead of the O(n) time that a linear scan would take. You simply do a binary search until the left and right choices are lower and higher than your number.

zerkms Over a year ago

@SubSevn: with sorted array - yes

alex Over a year ago

@SubSevn That would be after you profiled your application and determined this particular part of code to be the bottleneck, right? ;)

Sam Over a year ago

Nice solution, add an example also with for the number before, like $range = max(array_filter($ar, function($i) use($num) { return $i < $num; }));

|

mickmackusa · Accepted Answer · 2025-02-25 10:53:12Z

0

PHP8.4 gave birth to a new family of short circuiting functions -- one that suits your task perfectly. Demo

$ar = [0, 32, 64, 96, 128, 160, 192, 224];

$num = 44;

var_export(
    array_find($ar, fn($v) => $v > $num)
);
// 64

answered Feb 25 at 10:53

mickmackusa♦

49.2k13 gold badges98 silver badges165 bronze badges

Collectives™ on Stack Overflow

How to identify if given number is there in a given array range?

2 Answers 2

6 Comments

Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

6 Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related