# CS341 Advanced Topics in Algorithms (not taught from 17/18)

*CS341 15 CATS (7.5 ECTS) Term 2*

## Availability

Core - DM. Option - CS and CSys

## Prerequisites

CS260 Algorithms

## Academic Aims

To introduce students to new techniques, methods and results from the rapidly-developing field of algorithms. Typical topics include randomised algorithms, graph algorithms, matrix algorithms and counting algorithms. The module will be research-led, so exact topics will vary from year to year.

## Learning Outcomes

Students will be able to understand a variety of advanced algorithmic techniques, use recently-developed algorithmic techniques to solve problems, and understand the state of the art in some areas of algorithmic research, including new developments and open problems.

## Content

- Basic parallel computation models: circuits, comparison networks. Parallel merging and sorting by comparison networks.
- Advanced parallel computation models: PRAM, BSP.
- Fundamental parallel algorithms: total exchange, broadcast/combine, prefix sums, butterfly, grid.
- Further parallel algorithms: list and tree contraction, sorting, convex hull
- Parallel matrix algorithms: matrix-vector multiplication, matrix multiplication, triangular system solution, Gaussian elimination.
- Parallel graph algorithms: algebraic paths, all-pairs shortest paths, minimum spanning tree.

## Content in previous years.

- Sorting, selection, etc.
- Search trees, skip lists.
- Cuts, flows, approximation algorithms for graph problems.
- Online algorithms.

## Books

*Introduction to Algorithms*by Cormen, Leiserson, Rivest and Stein; in particular, Chapter 27 on Sorting Networks.*Parallel Scientific Computation: A Structured Approach using BSP and MPI*by Rob Bisseling. The official book website includes a freely downloadable introduction chapter, which gives a detailed description the BSP model.

## Assessment

Three-hour examination (80%), coursework (20%)

## Teaching

30 one-hour lectures, 4 Seminars