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BJP4 Exercise 11.13: isUnique

Language/Type: Java Collections Sets and Maps
Author: Marty Stepp (on 2016/09/08)

Write a method isUnique that accepts a Map from strings to strings as a parameter and returns true if no two keys map to the same value (and false if any two or more keys do map to the same value). For example, calling your method on the following map would return true: 

{Marty=Stepp, Stuart=Reges, Jessica=Miller, Amanda=Camp, Hal=Perkins}

Calling it on the following map would return false, because of two mappings for Perkins and Reges: 

{Kendrick=Perkins, Stuart=Reges, Jessica=Miller, Bruce=Reges, Hal=Perkins}

The empty map is considered to be unique, so your method should return true if passed an empty map.

Type your solution here:


This is a method problem. Write a Java method as described. Do not write a complete program or class; just the method(s) above.

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