You need numbers sooner than you expect, in a taxi, at a market stall, agreeing a time to meet. Algerian counting follows the same shape as other Arabic dialects up to ten, then simplifies.
The months are the part that surprises learners: Algeria uses the French names, so January is جانفي and February is فيفري, not the forms used further east. Say سبتمبر in Algiers and you will be understood; say كانون الثاني and you will not.
10 words to start with
واحد
waḥed
One
زوج
zuj
Two
Algerians say زوج zuj, not اثنين.
تلاتة
tlata
Three
ربعة
reb3a
Four
خمسة
khamsa
Five
ستّة
setta
Six
سبعة
seb3a
Seven
تمنية
tmenya
Eight
تسعة
tes3a
Nine
عشرة
3ashra
Ten
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