What are the rules for forming comparatives and superlatives of adjectives ending in -y?

What are the rules for forming comparatives and superlatives of adjectives ending in -y?

The rules for forming comparatives and superlatives of adjectives ending in -y are as follows:

1. For adjectives ending in -y with a consonant before it, the -y is changed to -i and -er is added for the comparative form, and -est is added for the superlative form.
Example: happy - happier - happiest

2. For adjectives ending in -y with a vowel before it, the -y remains unchanged and -er is added for the comparative form, and -est is added for the superlative form.
Example: easy - easier - easiest