###Explanation### How this works:

Explanation

How this works:

[' '(..4/++][' '(3*)))))][6`(2*.]['1'..++~][8 2?2/][' '(4/.(`\`\++~]['1'.+~2?10-][13( 1)?8(( 0)))))*-][6`(1)*]['('(4/2?][' '()]+++++++++++ 

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[' '(..4/++][' '(3*)))))][6`(2*.]['1'..++~][8 2?2/][' '(4/.(`\`\+~]['1'.+~2?10-][13(1)?8((0)))))*-][6`(1)*]['('(4/2?][' '()]+++++++++++ 

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###Explanation### How this works:

1. [' '(..4/++]
   1. ' '( converts the space to its ASCII code: 32.
   2. .. duplicates 32 twice. Now you have three times 32.
   3. 4/ divides the top 32 by 4. Now you have twice 32 and once 8.
   4. ++ adds up the 32, 32 and 8. You get 72, which is the ASCII code for H.
2. [' '(3*)))))]
   1. ' '( converts the space to 32.
   2. 3* multiplies the 32 with 3: 96
   3. ))))) increases 96 with 5, you get 101, which is the ASCII code for e.
3. [6`(2*.]
   1. 6`( gives the ASCII code of the char 6: 54
   2. 2* multiplies it with 2, you get 108, which is the ASCII code for l.
   3. . duplicates the l
4. ['1'..++~]
   1. '1'.. puts the char 1 on the stack and duplicates it twice.
   2. ++ concatenates the three chars and returns the string 111
   3. ~ converts it to the integer 111, which is the ASCII code for o
5. [8 2?2/]
   1. 8 2? calculates 8², you get 64
   2. 2/ divides it by 2, you get 32, which is the ASCII code for a space.
6. [' '(4/.(`\`\+~]
   1. ' '( converts the space to 32.
   2. 4/. divides it by 4, you get 8. The . duplicates it.
   3. (` decrements the second 8 and converts it to a string.
   4. \ swaps the top two elements. The 8 becomes the top element.
   5. ` converts the 8 to a string.
   6. \ swaps the top two elements. The 7 becomes the top element.
   7. + concatenates the two strings. You get 87 (as a string).
   8. ~ converts the string 87 to the integer 87, which is the ASCII code for W.
7. ['1'.+~2?10-]
   1. '1'. puts the char 1 on the stack and duplicates it.
   2. +~ concatenates the two chars to the string 11 and converts it to an integer.
   3. 2? calculates 11², you get 121.
   4. 10- decreases 121 with 10, you get the ASCII code for o: 111.
8. [13(1)?8((0)))))*-]
   1. 13( puts 12 on the stack.
   2. 1) puts 2 on the stack.
   3. ? calculates 12², you get 144.
   4. 8(( puts 6 on the stack.
   5. 0))))) puts 5 on the stack.
   6. * multiplies 6 and 5, you get 30.
   7. - substracts 144 with 30, you get 114, which is the ASCII code for r
9. [6`(1)*]
   1. 6`( converts 6 to a char and takes its ASCII code: 54
   2. 1)* multiplies 54 with 2, you get 108, the ASCII code of l
10. ['('(4/2?]
    1. '('( converts ( to its ASCII code, 40.
    2. 4/ divides 40 by 4, you get 10.
    3. 2? calculates 10², you get 100, which is the ASCII code for d
11. [' '()]
    1. ' '( converts the space to its ASCII code: 32
    2. ) increments the 32, you get 33, which is the ASCII code for !
12. +++++++++++ concatenates all ASCII codes to one string.