Kata

It's a Pokemon battle! Your task is to calculate the damage that a particular move would do using the following formula (not the actual one from the game):

damage = 50 * (attack / defense) * effectiveness

Where:

• attack = your attack power
• defense = the opponent's defense
• effectiveness = the effectiveness of the attack based on the matchup (see explanation below)

Effectiveness:

Attacks can be super effective, neutral, or not very effective depending on the matchup. For example, water would be super effective against fire, but not very effective against grass.

• Super effective: 2x damage
• Neutral: 1x damage
• Not very effective: 0.5x damage

To prevent this kata from being tedious, you'll only be dealing with four types: fire, water, grass, and electric. Here is the effectiveness of each matchup:

• fire > grass

• fire < water

• fire = electric

• water < grass

• water < electric

• grass = electric

For this kata, any type against itself is not very effective. Also, assume that the relationships between different types are symmetric (if A is super effective against B, then B is not very effective against A).

The function you must implement takes in:

1. your type
2. the opponent's type
3. your attack power
4. the opponent's defense