Do you know an English word with nine or more “u”s? Can you think of a word that contains the five vowels in order? How do computers search for such words from a dictionary?
On March 5, the Math Club of JerseySTEM hosted a lecture by Professor Alfred Aho (Department of Computer Science, Columbia University) in the New Providence Library. More than 70 students and parents from Chatham, New Providence, Summit, Berkeley Heights, Millburn and Scotch Plains crowded the lecture room.
Through fun examples, Professor Aho explained the construction of regular expressions, the magic tool that we can use to specify patterns in text strings. For example, with basic operations such as concatenation and arbitrary repetition of a wildcard symbol, a simple regular expression can capture the pattern of nine “u”s. Regular expressions appear throughout computer science such as in the design of compilers. Professor Aho also demonstrated that classic Unix commands such as egrep and modern programming languages such as Python use regular expressions to search for and match patterns in text strings.
In case you are wondering, humuhumunukunukuapuaa, a Hawaiian reef triggerfish, has nine “u”s! (Look for a youtube video to teach you how to pronounce the word.) For “abstemious”, the vowels a-e-i-o-u appear in order. Can you find more? As a homework exercise, Professor Aho challenged the students to find a long English word that is made up with distinct letters. His teaser was the 14-letter word “ambidextrously”.
Professor Aho’s lecture can be found on his webpage, http://www.cs.columbia.edu/~aho/Talks/17-03-05_STEM.pptx.
At the same event, the JerseySTEM Math Club also sponsored a book prize celebration for Sophie’s Math Corner (SMC), sophiescorner.jerseystem.net. Sophie Andrews, a sophomore from Chatham High School, runs SMC with the goal of providing math competition practice for middle school mathletes. At the event, Sophie presented books on the golden ratio as prizes to the top performers: Alec, Audrey and Spencer Thompson, Jason and Julia Li, Om Desai, Gyan Ghoda and Stephen Andrews. Congratulations!