CODEWITHSUNDEEP
java
membersound
membersound

Reputation: 86747

How to create mappings between different numbers?

I'd like to create a mapping for ratings based on numbers. Each "original" number should get assigned a bunch of "target" numbers

Similar to this:

 if (i = 2) return 3;
 if (i = 3) return 5;
 if (i = 4) return 7;

And so forth. How could I best write these sort of mappings, without having to repeatedly create ´if-return` statements?

Upvotes: 2

Views: 89

Answers (2)

jluckin
jluckin

Reputation: 662

For your problem, there are two main solutions.

The first one is to take the three pairs of numbers that you give and put them into a Map. A map associates a key with a value, so you would put each pair into your map

HashMap<Integer, Integer> myMap = new HashMap();
myMap.put(myKey, myValue);

To get myValue from the map, you would access it through myMap.get(myKey)

The other way to do this is to note that the numbers that you give follow a function. 2x-1. You can create a function in the code to mimic this behavior

int myFunction(int value) {
    return 2*value-1;
}

Just call this function and you will get the correct output. For example myFunction(3) will return 5.

Upvotes: 2

Genzotto
Genzotto

Reputation: 1974

Map<Integer, Integer> mappings = new HashMap<Integer, Integer>();
mappings.put(2,3);
mappings.put(3,5);
mappings.put(4,7);
System.out.println(mappings.get(2));
System.out.println(mappings.get(3));
System.out.println(mappings.get(4));

Upvotes: 6

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