Compare and contrast the Mauryan Empire and the Gupta Empire

The Mauryan Empire was established in 322 BCE by Chandragupta. He established a centralized government, under which trade and communication flourished. Ashoka was the third and most famous of the Mauryan emperors (who promoted Buddhism).
After Ashoka died, the empire suffered an attack by the Greeks, and later the Scythians, which resulted in a disunited India for another five centuries.
The Gupta Empire was founded by Sri Gupta in about 320 CE, and emulated the Mauryan Empire as the most recent instantiation of consolidated rule of the Indian subcontinent. One ruler even renamed himself Chandragupta. The empire ultimately fell owing to weak rulers coupled with attacks by the Huns around 500 CE.
Similarities include the promotion of trade, the unification of modern India, and initially strong rulers. Differences include religion (the Mauryan empire being Buddhist, and the Gupta empire being Hindu), as well as the reasons for their declines (Ashoka's death precipitated the downfall of the Mauryan Empire, and the Hunnic invasion brought about the destruction of the Gupta Empire). Lastly, the cultural impacts of the Gupta empire included the invention of the decimal system (and the number "zero"), and the legacy of the Mauryan empire is of military might.