Excel: Increment Numbers Based on Another Column(Criteria) when Value Changes | Windows

apple	1
apple	2
apple	3
mango	1
mango	2
coco	1
coco	2
coco	3
coco	4
vanila	1
vanila	2

=IF(B10<>B9,1,C9+1)

or

=COUNTIF($A$2:A2,A2) 

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