an ▁Category : I sl am ic ▁organizations ▁Category : Rel ig ious ▁organis ations ▁based ▁in ▁Sa udi ▁Arab ia ▁Category : I sl am ▁and ▁science <0x0A> </s> ▁Ver bal ▁arithmetic , ▁also ▁known ▁as ▁al ph am et ics , ▁ ▁crypt ar ithmetic , ▁crypt arith m ▁or ▁word ▁addition , ▁is ▁a ▁type ▁of ▁mathematical ▁game ▁consisting ▁of ▁a ▁mathematical ▁equation ▁among ▁unknown ▁numbers , ▁whose ▁digits ▁are ▁represented ▁by ▁letters . ▁ ▁The ▁goal ▁is ▁to ▁identify ▁the ▁value ▁of ▁each ▁letter . ▁ ▁The ▁name ▁can ▁be ▁extended ▁to ▁puzz les ▁that ▁use ▁non - alph ab etic ▁symbols ▁instead ▁of ▁letters . ▁ ▁The ▁equation ▁is ▁typically ▁a ▁basic ▁operation ▁of ▁arithmetic , ▁such ▁as ▁addition , ▁multiplication , ▁or ▁division . ▁ ▁The ▁classic ▁example , ▁published ▁in ▁the ▁July ▁ 1 9 2 4 ▁issue ▁of ▁Str and ▁Magazine ▁by ▁Henry ▁D uden ey , ▁is : ▁ ▁The ▁solution ▁to ▁this ▁puzz le ▁is ▁O ▁= ▁ 0 , ▁M ▁= ▁ 1 , ▁Y ▁= ▁ 2 , ▁E ▁= ▁ 5 , ▁N ▁= ▁ 6 , ▁D ▁= ▁ 7 , ▁R ▁= ▁ 8 , ▁and ▁S ▁= ▁ 9 . ▁ ▁Trad itionally , ▁each ▁letter ▁should ▁represent ▁a ▁different ▁digit , ▁and ▁( as ▁in ▁ordinary ▁arithmetic ▁notation ) ▁the ▁leading ▁digit ▁of ▁a ▁multi - digit ▁number ▁must ▁not ▁be ▁zero . ▁ ▁A ▁good ▁puzz le ▁should ▁have ▁a ▁unique ▁solution , ▁and ▁the