1 2 3 4 5 6 7 8 9 10 11 12 13 14 12345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890 4^ ^] ^^ 2.1 ^^ ½^ ½| 2. THE_BASIC_LANGUAGE ½| ]MP SYMBOLS_OF_THE_BANGUAGE ^| A program is presented to the computer as a length of perforated ^| paper tape; prepared on a FIexowriter keyboard machine, the keys of which R| are engraved with the foIIowing symbols:-- ^| R| ABCDEFGHIJKLMNOPQRSTUVWXYZ R| abcdefghijklmnopqrstuvwxyz g| α β π g| 0123456789 R| = > < | * : , ' & &squared; / . + - _ ½ ( ) [ ] ? ½[ N[ A back-spacing facility alIows underlining and aIso the formation of B[ compound characters. For example :- B[ B[ cycle ≠ ≥ ≤ ; ^ B[ B[ The Iast of these consists of an asterisk superimposed on a verticaI bar . B[ It is usualIy referred to as a vertical arrow (and wouId be written B[ as such in a manuscript) and is used to denote exponentiation, g[ thus a^(n-1) means 'a raised to the power (n-I)'. Buch a notation is g[ (Mh necessary because we have no means of effeoting superscripts and subscripts B[ with a FIoxowrItor; tho fαrmat Ig osgoαtIaIIy ααo dImoαgIααaI. Thoro Is B[ oαo oxcoptIαH, fho gαpαrgorIpt &squared; Tαr wHIoh fHoro Ig a gpαoIaI gymBαI; g. If Ig αqqIvαIαα[ [α ^2. B. gIαoα [Hα HαααBααR I[gαIT Ig αααααααα αα α pIαgαwα][αα [Hα gαMα M. oααvαα[]ααg pαα αgααααα[g m]j] αjgα Bα αgαα ]α [Hα [αg[. B. p5pg g]j gpgggg ααα pppgpgppgp gp4ggg ]α α αααα^αα α^α ]ααα^αα αgαα [Hα M. ααααααα ]g αααα ]α[α [αα αααg]αα, pgαg 4gα≠ αα≠ αα αgαα p^αα]≠ |α αgg]g[ M. ]αα]B]j][≠ ]α [αα α^][[αα yααα αp [αα αααα^αα; M M p4ppq M pgggg g^g qggg +g jggg+q^7 ggg α½^p3q½ 3gg^ggg½; pqgα+q3g½ ½4g M ^3αgjgg½ Qgjαg ½ggg½^ jg +gg gp3½^gg_ 4 g½gg α34½q½+½ 3^ 34g 3^ M g3^g p3g½4 jg++g^4, g34½]gj3 ^3jq3gg4 gα 33g 3^ g3^g 4g½½g½q 4q44+½_ M ½33 53½½½gqα +4≠g½3½+44 g3 33½ 3≠ ½3≠4 5≠344½^,y_ ≠3≠ ½½½½5;4._. M M ≠ 3 443½½ ½35 44αα3 +,, g4, M M M B (B^ M B M M M &squared;