Meaning of Merge[A[1,..n], m] I was reading JeffE's (Prof. Jeffrey Erickson) notes on solving recurrences, and he used Merge[A[1,...n], m] where A is an array(I think) and m is an integer. What does this mean? I thought Merge sort took two arrays as input. He includes psuedo code, but I can't decipher what is means. What is it doing?

Thank you for any help.

Link: 
http://jeffe.cs.illinois.edu/teaching/algorithms/notes/99-recurrences.pdf
$Merge[A[1,...n], m]$ means merge arrays $A[1..m]$ and $A[m+1..n]$.

They are recursively sorted before merging by 

MergeSort(A[1 .. m])
MergeSort(A[m + 1 .. n])