Irish Snap: Variant Rules

Question

Introduction

Recently, me and a couple of my friends decided to play some cards, and one of them suggested the game 'Irish Snap', which was the inspiration for this challenge. However, I later learnt that the game has a lot of different rules that you can play with, some of which are listed here. The rules that are in this challenge aren't currently listed on that page, hence the name, 'Variant Rules'

The Challenge

Given an array of 3 cards, output a truthy or falsey value depending on if they make a valid snap in a game of Irish snap.

Input

The input will be an array of 3 numbers, ranging from 1-13 inclusive, with 1 representing an ace, 11 representing a jack, 12 representing a queen and 13 representing a king. The input can be in any order of top, middle, bottom.

Rules

The 4 different criteria for if cards make an Irish snap are:

• The top and middle cards are the same
• The top and middle cards have a difference of one
• The top and bottom cards are the same
• The top and bottom cards have a difference of one

If any of these criteria are met, you must output a truthy value. As well as this, for the two criteria that require the cards to have a difference of one, it 'wraps around', meaning that an ace and a king are considered to have a difference of one, and vice versa.

Test Cases

Input (Bottom, Middle, Top) -> Output
1 13 7 -> False
1 4 13 -> True
9 3 6 -> False
8 9 7 -> True
2 6 5 -> True
12 5 11 -> True
10 4 8 -> False
12 13 7 -> False
9 7 10 -> True
7 3 1 -> False
4 2 3 -> True

Answer 1

Perl 6, 16 bytes

3>(*-(*|*)+1)%13

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Anonymous whatever lambda that takes input as top, middle, bottom and returns a Junction that evaluates to True or False

Answer 2

Python 3, 38 bytes

lambda x,y,z:{x-y,x-z}&{0,1,12,-1,-12}

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Returns a non-empty set (truthy) if valid, empty set (falsey) if not. Takes input in order top-middle-bottom, but can be rearranged for same code size.

Answer 3

05AB1E, 7 6 bytes

α12%ß!

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Takes inputs as [middle, bottom], top.

α        # absolute difference
 12%     # mod 12
    ß    # minimum
     !   # factorial

Only 1 is truthy in 05AB1E. 0! and 1! are both 1, while no other number has a factorial of 1.

Answer 4

J, 12 bytes

1 e.2>12||@-

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Taking bottom middle as left arg, top as right arg.

original answer taking input as one list

J, 24 bytes

1 e.2>#:@3 5(12||@-/)@#]

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• #:@3 5 The numbers 3 and 5 in binary are 0 1 1 and 1 0 1 which are the masks for the middle/top and bottom/top cards respectively
• (12||@-/)@# We filter the input with those masks, take the abs value of the resulting differences, then the remainder when divided by 12 (for the ace-king case)
• 1 e.2> are either of the resulting numbers less than 2, ie, 0 or 1?

Answer 5

JavaScript (ES6), 29 bytes

Takes input as ([bottom, middle])(top).

The output is inverted.

a=>c=>a.every(n=>(n-c)/2%6|0)

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---

JavaScript (ES6),  37  30 bytes

Saved 1 byte thanks to @Grimy

Takes input as ([bottom, middle])(top).

a=>c=>a.some(n=>(n-=c)*n%72<2)

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Answer 6

Charcoal, 12 bytes

›²⌊﹪↔⁻Ｅ²ＮＮ¹²

Try it online! Port of @Grimy's answer. Takes input as three separate values bottom, middle, top, and outputs using Charcoal's default Boolean format of - for true, nothing for false. Explanation:

 ²              Literal 2
›               Is greater than
  ⌊             Minimum of
    ↔            Absolute value of (vectorised)
      Ｅ²Ｎ       First two numeric inputs as a list ([bottom, middle])
     ⁻          Minus (vectorised)
         Ｎ      Third input (top)
   ﹪            Modulo (vectorised)
          ¹²    Literal 12

Answer 7

Pyth, 12 11 bytes

Takes input as [bottom, top, middle] or [middle, top, bottom] (both work). Outputs [] (Falsy in Pyth) if there's no valid snap, a non-empty array otherwise.

f>2%.aT12.+

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If a consistent truthy/falsy value is required, add .A in front for +2 bytes. Then output will be True or False.

Explanation

  f             # Filter on lambda T:
   >2           # 2 > 
      .aT       #     abs(T)
     %   12     #            % 12
           .+   # the list of deltas (difference between consecutive elements)

.A (if required)# Any truthy values in the above list?

Edit: -1 with a different approach

Answer 8

Perl 5 -ap, 31 bytes

$t=<>}{$\|=abs($t-$_)%12<2for@F

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Input:

bottom middle
top

Actually, the order of the middle and bottom doesn't matter.

Output:

0 for false; 1 for true

Answer 9

Jelly, 6 bytes

ạ%12ṠƑ

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Answer 10

C (gcc), 47 43 bytes

f(b,m,t){return(1<<t-m|1<<t-b)&0x80101003;}

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Answer 11

Japt, 7 bytes

d_aV <2

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Answer 12

T-SQL 2008, 40 bytes

PRINT 1/-~abs((@-@2)%12/2*((@-@3)%12/2))

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Answer 13

Jelly, 6 bytes

I%12ỊẸ

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A monadic link taking the list of [middle, top, bottom] as its argument and returning 1 for snap and 0 for no snap.

Answer 14

[R], 23 bytes

takes input as a=c(bottom,top,middle):

any(abs(diff(a))%%12<2)