lecture1 - 6.006- Introduction to Algorithms Lecture 1...

6.006-
Introduction to
Algorithms
Lecture 1
Prof. Constantinos Daskalakis

Today’s Menu
• Motivation
• Administrivia
• Course Overview
• Linked Lists and Document Distance
• Intro to “Peak Finding”

“Al -go-rithms ”… wha?
• Remember Logarithms?
– they have nothing to do with Algorithms
• Well specified method for solving a problem u
sing a finite sequence of instructions
• Description might be English, Pseudocode, or
real code
• Key: no ambiguity

Al- Khwārizmī (780-850)

Efficient Algorithms: Why?
• Solving problems consumes resources that are
often limited/valuable:
– Time: Plan a flight path
– Space: Query a database
– Energy: Save money
• Bigger problems consume more resources
• Need algorithms that “scale” to large inputs,
e.g. searching the web…

Efficient Algorithms: How?
• Define problem:
– Unambiguous description of desired result
• Abstract irrelevant detail
– “ Assume the cow is a sphere”
• Pull techniques from the “ algorithmic toolbox”
– [CLRS] class textbook
• Implement and evaluate performance
– Revise problem/abstraction
• Generalize
– Algorithm to apply to broad class of problems

Administrivia
• Handout: course info
• Profs: Daskalakis, Jaillet
• TAs: Goldstein, Griner, Bhattacharya, Madry
• Sign up for class at