tvl-depot/users/wpcarro/scratch/facebook/recursion-and-dynamic-programming/magic-index.py

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from math import floor
def find_magic_index_brute(xs):
for i in range(len(xs)):
if xs[i] == i:
return i
return -1
def mid(lo, hi):
return lo + floor((hi - lo) / 2)
def find_magic_index(xs):
lo, hi = 0, len(xs) - 1
return do_find_magic_index(xs, 0, len(xs) - 1)
def do_find_magic_index(xs, lo, hi):
pass
xss = [
[],
[-1,0,2,4,5,6],
[1,1,1,1,1,5],
[-2,-2,-2,-2,4],
[1,2,3,4,5],
]
for xs in xss:
print(xs)
a = find_magic_index_brute(xs)
b = find_magic_index(xs)
print(a, b)
assert a == b
print("Success!")