def find_pairs(array):
if len(array) < 2:
return []
else:
output = []
zero_count = 0
for item in array:
if item == 0:
zero_count += 1
if zero_count > 1:
output.append((0, 0))
mymap = HashMap()
for item in array:
mymap.put(-item, item)
for item in array:
if mymap.contains_key(item):
if item != 0:
output.append((item, -item))
mymap.remove(item)
mymap.remove(-item)
return output
