I have been searching for mergesort implimentations in python and came across this.
def merge(a, b): if len(a)*len(b) == 0: return a+b v = (a[0] < b[0] and a or b).pop(0) return [v] + merge(a, b) def mergesort(lst): if len(lst) < 2: return lst m = len(lst)/2 return merge(mergesort(lst[:m]), mergesort(lst[m:])) mlst = [10, 9, 8, 4, 5, 6, 7, 3, 2, 1] sorted = mergesort(mlst) print sorted Besides using recursion in merge function also, it has somethings intresting. Especially the statement v = (a[0] < b[0] and a or b).pop(0) gives a.pop(0), if a[0] < b[0] otherwise b.pop(0). We have to look at the statement as v = ((a[0] < b[0] and a) or b).pop(0) regards, Sarma.
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