What is a 'Greedy' algorithm?

What is a 'Greedy' algorithm?

Approach: Describe making the locally optimal choice at each step.

An algorithmic paradigm that follows the problem-solving heuristic of making the locally optimal choice at each stage with the intent of finding a global optimum.

Follow-up: Does it always find the global optimum?

Key concepts: local optimum, global optimum, heuristics.