from collections import Counter
data = [1, 2, 1, 1, 0, 0, 3]
success = []
fail = []
counter = Counter(data)
for i in data:
if not counter[i]:
continue
counter[i] -= 1
if counter[2 - i]:
counter[2 - i] -= 1
success.append((i, 2 - i))
else:
fail.append(i)
print(success, fail)
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