In chart, a, b and c is zigzag which very easy to understand by picture.
Its really easy to understand this wave counting if you read just below basic rules and Characteristics of Zigzags.
Rules: - Wave A always subdivides into an impulse or leading diagonal . -Wave A always subdivides into an impulse or leading diagonal . - Wave B always subdivides into a zigzag , flat, triangle or combination. - Wave C always subdivides into an impulse or diagonal triangle.