def minby(f, l):
best, bestval = car(l), f(car(l))
for x in cdr(l):
val = f(x)
if val < bestval:
best, bestval = x, val
return best
def pairwise(l):
'Only works for lists up to 1000 in size. snide Python comment goes here'
if not l:
return []
else:
return [(car(l),x) for x in cdr(l)] + pairwise(cdr(l))
