Practice Stream Reduction (5.9) - Java Streams and Lambda Expressions

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6 sample questions

Question 1.
What does the reduce() method do?
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Think about combining elements.
Question 2.
What does the identity value in reduce() represent?
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It's the starting point in our calculation.
3Question 3.
What is the primary purpose of the reduce() method in Java Streams?
- To filter elements
- To combine elements into a single result
- To sort elements
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Think about aggregation.
4Question 4.
True or False: The identity value can be any number you want.
- True
- False
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Consider what operations we can perform.
Question 5.
You have a list of purchase prices. Write a Java program that calculates the total cost after applying tax. Assume a tax rate of 0.07 and the prices are represented in a List. Use reduction for the calculation.
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Consider using a decimal for the total.
Question 6.
Explain how you would use reduce() to combine the lengths of names in a list into one string.
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Think about initializing with an empty string and adding lengths.

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