xor to find unpaired

find_unpaired.py

# python:
def find_unpaired(xs):
	"""find unpaired element with array of 2n + 1 elements"""
	for i in range(1, len(xs)):
		xs[i] ^= xs[i - 1]
	print(xs[len(xs) - 1])  
# pseudocode:
fun findUnpaired(aList):
	#N - length of input list
	for i from 1 to N:
		aList[i] ^= aList[i - 1]
	print(aList[N - 1])