Running Times - SIGCSE 2021

Searching an array of a values is a bit like checking what's behind door number 1 (or 0) followed by door number i, which sounds a bit like Let's Make a Deal. So why not approach it as such? We present an introduction to arrays, linear search, and binary search that typically involves inviting one or two students to the front of the class to search a pair of arrays, unordered and ordered. The array itself can be implemented with pieces of paper taped to the board, behind which are numbers in chalk, or as HTML divs on a touchscreen instead, or even as actual doors. Sometimes the demo goes well, with one search taking n steps and the other log n. Sometimes the students get lucky, and both take just 1! With a bit of planning or choreography, though, the intended points can be made. And quite often do students' classmates start rooting for them along the way.

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David J. Malan

[JOJOSHgaming]

I love how he explains even such fundamental algorithms passionately with wonderful illustrations.

[tonywoy]

I remember in one of the years, one student kept guessing luckily the correct number in the random search and it was hillarious

[darkmuha]

I love how he wants to pick a student so bad that he broke the 4th wall 😂

[sukhbir_virdi]

we love you sir😍😍😍
the way of your teaching👍👍

[TURKISTONIM]

Thanks you my teacher you giving me valuable knowledge 😉 thanks again

[adityaheart]

I really want to know how can i improve my English? Can you please tell me ??

[damianbruntz]

Slow down Master. Perhaps not your whole entire audience is native english speaker...