Substitute Algorithm

This is when you replace the algorithm with the new algorithm. Here is another good reason for keeping algorithms within a method.

   String foundPerson(String[] people){
       for (int i = 0; i < people.length; i++) {
           if (people[i].equals ("Don")){
               return "Don";
           }
           if (people[i].equals ("John")){
               return "John";
           }
           if (people[i].equals ("Kent")){
               return "Kent";
           }
       }
       return "";
   }

   String foundPerson(String[] people){
       List candidates = Arrays.asList(new String[] {"Don", "John", "Kent"});
       for (int i=0; i<people.length; i++)
           if (candidates.contains(people[i]))
               return people[i];
       return "";
   }

Additional Resources

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