Aristotle was a student of Plato for about two decades at the Academy of Athens. He was a member of the Academy at the age of 17 until the death of Plato in 347 BCE. Even though he went on to establish his own philosophical system, Aristotelianism, which challenged Plato's Theory of Forms in many ways, his early education was heavily influenced by Plato.
Socrates was the teacher of Plato
Alexander the Great was actually a student of Aristotle, who was invited by King Philip II of Macedon to tutor the young prince.
Heraclitus was a pre-Socratic philosopher who lived before Aristotle's time.