Amazon coding test

amazon.py

#!/usr/bin/env python
import sys

N,K = (int(val) for val in sys.stdin.readline().split())
setN = [int(val) for val in sys.stdin.read().split()]

# Should we check len(setN) <= N?

# We should sort such that we can optimise
setN.sort()

# Ok, so bruteforce is O(n) - try set intersection for cardinality?
matchSet = [i + K for i in setN]
print len(set(setN).intersection(set(matchSet)))

print setN
print matchSet

I can't remember where I read about this challenge but yeah - this would be what I'd expect from it.