What is basic difference between fold and reduce in Kotlin? When to use which?

The main differences between fold and reduce in Kotlin are:

1. fold takes an initial value as a parameter, whereas reduce starts the accumulation with the first element of the collection[1][2][3].

2. fold can be safely called on an empty collection and will return the initial value, while reduce will throw an exception on an empty collection[4].

3. The result type of reduce is always the same as the element type of the collection, while fold can return any type based on the initial value[1][2].

When to use each:

• Use fold when you need to specify an initial value for the accumulation, or when the first element of the collection cannot be the first value of the accumulator[4].

• Use reduce when you want a concise way to accumulate values without specifying an initial value, and when the result type should be the same as the element type[1][2].

For example, t...