Regex Formula (Multiples of 25?)

[miminsy]

This may not be entire related but I'm trying to find a regular expression that will pick up integer numbers ending with multiples of 25. e.g. 25, 50, 75, 100, 125, 150, 175, 200 etc.. you get the idea. 

However, the problem remains that the regex doesn't work and I'm a total noob at this 

This is the formula I found and edited a bit to try and make it work

^(?!0\d)+\b((25)|(50)|(75)|(00))$

But the problem is that... it only matches the expression if it's 25, 75, 50 or 00. I have no idea how to make it such that the digits before the last 2 are all accepted? It would be great if anyone could help me with this! Thank you so much!

[Peter]

I personally wouldn't try and write a regular expression for this problem. I would instead use the modulo division operator.

Example:

var num = 25;

while(num <= 1000){
if(num % 25 == 0){
console.log(num);
}

num ++;
}

[Lynx]

If you're not familiar with modulus, it basically means that you want the remainder of a division. For example, 25/4 equals 6 with a remainder of 1. The remainder (1, in this case) is your modulus.

With Peter's example above, it's taking every number from 25 (initial value of num) to 1000, inclusive, (found in the while loop) and dividing that number by 25. If the remainder is 0, this means that the number is evenly divisible by 25 (since there is no remainder) - thus making it a multiple of 25.

[Kami]

For some minor clarification, that's every number starting at 25 that is less than or equal to ( <= ) 1000 (so 1000 would be included in that). I'm sure that is what MSG meant but I wanted to make doubly sure it was understood.

[Lynx]

Thanks, Kami.

I edited my post above to add the word inclusive.

[Todge]

If you really want to use RegExp, try

^\d+(25|50|75|00)$

[Quozzo]

Feb 14, 2017 14:58:02 GMT -8 Todge said:

If you really want to use RegExp, try

^\d+(25|50|75|00)$

Hate to nitpick but ^\d*(25|50|75|00)$would be best as it would also match 25, 50, 75 and 00.

[Former Member]

Those regular expressions are not greedy enough, so the modulo is a better implementation.

[Quozzo]

The modulo cycles through each number in a loop and displays those that are multiples of 25. The RegEx would match numbers in already existing text such as post. If the whole post wanted to be scanned for matches then drop the start and end of string symbols and include the global flag like so.

/\d*(25|50|75|00)/g

[Peter]

Both methods are a fine solution for the original question, as we do not know the input (poster didn't specify that). If it is a mixed value, then I agree that the regular expression would be better, otherwise modulo would be the better option for a single value type.

[Former Member]

The modulo is used for Math(integer) calculations, is that not what the OP wanted? Or did I miss something?

[Peter]

@synthtec,

When I first read the question, I thought the same thing as you, hence the reason for not given a regular expression as a solution.

Until the OP responds, guess we will never know

[Former Member]

Well, both yourself Peter and Quozzo have given the correct solution to both, so the question was answered in my mind.

[Lynx]

miminsy,

Has any of the solutions above worked for you? If not, could you elaborate more on how you need it to function?