Re: Challenge 3 The Runner-Up

[SJT]

 

q)list1:4 7 9 7 2 8 9 
q)ru:@[;1] desc distinct:: /runner-up 
q)ru list1 
8

 

Using general list notation (items separated by semicolons and embraced by parentheses) suggests a list is general; better to write a vector as a vector literal.

Composition ru is a sequence of three unaries. In evaluation order: select the distinct items; sort descending; select second item.