# Count occurrences of an integer [closed]

Based on the question How many positive integers < 1,000,000 contain the digit 2?. I'm looking for the most creative solution to count all the Integers from X to Y containing the Integer Z. Z can be from 0 to Y.

Every found Integer only counts once, even if the integer Z appears more often. For example:

Z = 2
123 counts 1
22222 also counts 1


I will start with a really simple algorithm written in Java (because it's beloved by everyone):

public class Count {
public static void main(String[] args) {
int count = 0;
for (int i = Integer.parseInt(args); i <= Integer.parseInt(args); i++) {
if (Integer.toString(i).contains(args)) {
count++;
}
}
System.out.println(count);
}
}


if you run this with

java -jar Count.jar 0 1000000 2


you get this as the result:

468559


Because this problem is not hard to solve it's just a . Most upvoted answer posted by 28th of February wins!

• It's not entirely clear from your post, but I guess Z can be between 0 and inf? Or just between 0 and 9? – mmumboss Feb 10 '14 at 11:21
• Z can be between 0 and Y. It doesn't make sense that Z can be bigger than Y. – Obl Tobl Feb 10 '14 at 11:31
• @OblTobl Do you really want to explicitly exclude the Z>Y case? Why not just have expected output in that case be 0? – Cruncher Feb 10 '14 at 16:14
• @Cruncher i don't mind! but it's a little bit useless i think ;-) – Obl Tobl Feb 10 '14 at 16:24
• Does this mean that N can be 123 and it would only match if the substring 123 exists? – Populus Feb 10 '14 at 16:40

# Haskell (56 code, 16 import)

Thought I'd throw a little Haskell version into the mix!

import Data.List
c x y z=length$filter(isInfixOf(show z))$map show$[x..y]  It can be shorter if we are allowed to require that z be input as a string: import Data.List c x y z=length$filter(isInfixOf z)$map show$[x..y]


Usage:

> c 0 1000000 2
468559


# k (28)

{+/($x+!y-x)like,/3#"*",,$z}


Takes three arguments, like this:

  {+/($x+!y-x)like,/3#"*",,$z}[0;1000000;42]
49401


## Javascript - 55 54 chars (Loop)

### (Shortest JS solution!)

Edit: 12/Feb/14 - Updated search condition - 1 char reduced

a=(x,y,z,c)=>{while(x<=y)c+=(x+++'').search(z)+1?1:0}


Using the new fat arrow notation.

Usage: a(1,20,2,0),c gives 3 (Note the fourth argument is compulsorily set to 0 and don't forget the ,c also. Just some work to save chars ;) ).

### Javascript - 62 61 chars (Recursive)

Edit: 12/Feb/14 - Updated search condition - 1 char reduced

c=0
a=(x,y,z)=>{if(x<=y)c+=(x+'').search(z)+1?1:0,a(x+1,y,z)}


Usage: a(1,20,2),c gives 3

Feedback appreciated!

• @ Everyone Just to let know, I miscounted the chars of recursive version. They are 62 instead of 72 :P Fixed. – Gaurang Tandon Feb 11 '14 at 16:30

# perl [41 chars]

print 0+grep/$ARGV/,$ARGV..$ARGV  Run: > perl -le 'print 0+grep/$ARGV/,$ARGV..$ARGV' 2 0 1000000
468559

• Actually this are 43 needed chars. – Leo Pflug Feb 12 '14 at 9:44
• You can remove the brackets () around the range, then it would be 41 chars. – Leo Pflug Feb 12 '14 at 9:58
• sorry, my counting sucks. but thanks for the shortening – Tom Tanner Feb 12 '14 at 11:51
• @LeoPflug your code doesn't work - try giving it '22' as the search parameter (i don't have enough rep to comment on your post), and also try giving it 1000 as the lower limit. – Tom Tanner Feb 12 '14 at 12:03
• Thanks, now it works again. Although I still have to fix the lower limit, damn ... Should have used test cases. :( – Leo Pflug Feb 12 '14 at 12:07

Perl - 44 chars

$x+=/$ARGV/ for$ARGV..$ARGV;print\$x


Usage

C:\strawberry\projects>perl county.pl 0 1000000 2
468559


My first golf with Perl(I'm learning it currently) so I'm open for suggestions! I'd appreciate them.

• Okay, just saw after posting this, that one already posted a good golf with perl. atleast I was close! Will use grep in future since I understand it now after this example. :D – Leo Pflug Feb 12 '14 at 9:21
• After some edits I beat the other one golfing with perl! – Leo Pflug Feb 12 '14 at 10:59
• After fixing bugs I'm behind again. yey~ – Leo Pflug Feb 12 '14 at 12:18

# Golfscript - 18

My contribution in golfscript

:i;,\>{i?1+},,


Explaination:

:i;        #Convert Z to string, store in i, and pop
,\>         #Generate range 0 ... Y and then remove values < X
{i?1+},    #Filter all non-matches out of the array
,           #Count the number of values in the array


Try it here

# Javascript

function f(s,e,n){for(r=0;e-->s;){if(~(''+e).indexOf(n))r++}return r}


f(0,1e6,2) returns 468559

What is --> operator ? Not an operator

• Since you are leaking return variable r to the global scope, one could omit the return.. – GitaarLAB Feb 11 '14 at 5:40
• Also you can save a char by using a for loop. function f(s,e,n){for(r=0;e-->s;){if(e.toString().indexOf(n)>=0)r++}return r} – Danny Feb 11 '14 at 15:22
• You can also change e.toString() to (e+'') and (...)>=0 to ~(...). – Noyo Feb 15 '14 at 12:00

## TI-BASIC

As usual, -> represents the STO-> arrow:

:0->I
:Prompt X,Y,Z
:randIntNoRep(X,Y)
:Z=Ans
:cumSum(Ans)


Let's try it out:

X=?1
Y=?10
Z=?2
1
Done
`
• This does not work. the Z=Ans line will return zero if the number is not exactly the same. It will for example not recognize the 2 in 12. – mmumboss Feb 10 '14 at 12:14