+⌿÷≢ +⌿÷≢

0.1±×÷⌈⌊*⍟|!○~∨∧⍱⍲<≤=≥>≠.@≡≢⍴,⍪⍳↑↓?⍒⍋⍉⌽⊖∊⊥⊤⍎⍕⌹⊂⊃∪∩⍷⌷∘→←⎕⍞/⌿\⍀À¨⍣&⍨⌶#⊆⍥⊣⊢⍠⍤⌸⌺⍸()[];⍝⋄:⍬{}∇ 0.1+-×÷⌈⌊*⍟|!○~∨∧⍱⍲<≤=≥>≠.@≡≢⍴,⍪⍳↑↓?⍒⍋⍉⌽⊖∊⊥⊤⍎⍕⌹⊂⊃∪∩⍷⌷∘→←⎕⍞/⌿\⍀À¨⍣&⍨⌶#⊆⍥⊣⊢⍠⍤⌸⌺⍸()[];⋄:⍬{}∇⍝

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0.1+-×÷⌈⌊*⍟|!○~∨∧⍱⍲<≤=≥>≠ .@≡≢⍴,⍪⍳↑↓?⍒⍋⍉⌽⊖∊⊥⊤⍎⍕⌹⊂⊃∪∩⍷⌷∘→←⎕⍞/⌿\⍀À¨⍣&⍨⌶#⊆⍥⊣⊢⍠⍤⌸⌺⍸()[];⋄:⍬{}∇⍝

≢ often renders as ≡/

Samples:

APL (named after the book A Programming Language)^[2] is a programming language developed in the 1960s by Kenneth E. Iverson. Its central datatype is the multidimensional array. It uses a large range of special graphic symbols^[3] to represent most functions and operators, leading to very concise code. It has been an important influence on the development of concept modeling, spreadsheets, functional programming,^[4] and computer math packages.^[5] It has also inspired several other programming languages.^[6][7]

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xtimes←{⎕IO←0  ⍝ Fast multi-digit product using FFT.

    roots←{×\1,1↓(⍵÷2)⍴¯1*2÷⍵}

    cube←{⍵⍴⍨2⍴⍨2⍟⍴⍵}

    extend←{(2*⌈2⍟¯1+(⍴⍺)+⍴⍵)↑¨⍺ ⍵}

    floop←{(⊣/⍺)∇⍣(×m)⊢(+⌿⍵),[m-0.5]⍺×[⍳m←≢⍴⍺]-⌿⍵}

    FFT←{,(cube roots⍴⍵)floop cube ⍵}

    iFFT←{(⍴⍵)÷⍨,(cube+roots⍴⍵)floop cube ⍵}

    rconvolve←{(¯1+(⍴⍺)+⍴⍵)↑iFFT⊃×/FFT¨⍺ extend ⍵}

    carry←{1↓+⌿1 0⌽0,0 10⊤⍵}

    (+/∧\0=t)↓t←carry⍣≡0,⌊0.5+9○⍺ rconvolve ⍵

}