JavaScript - Array Methods

Question 1

Reduce method is the most ___ of all array operations

Answer 1

general

Question 2

Reduce returns

Answer 2

a single value

Question 3

Reduce accepts ____ as argument

Answer 3

callback function, called the reducer

Question 4

Arguments the reducer function takes…

Answer 4

Accumulator (acc)
Current Value (cur)
Current Index( idx)
Source Array (src)

Question 5

Optional argument to the reducer

Answer 5

initialValue

Question 6

the first time the callback is called in reduce, accumulator and currentValue

Answer 6

if initialValue is provided, then accumulator = initialValue and currentValue = arr[0]

if no initialValue, then accumulator = arr[0], and currentValue = arr[1]

Question 7

It is _____ an initialValue

Answer 7

almost always safer to provide