Find unique triplets in the list (a+b+c=0)ΒΆ
Find unique triplets whose three elements gives
the sum of zero from an array of N integers.
def three_sum(nums):
result = []
nums.sort()
for i in range(len(nums)-2):
if i > 0 and nums[i] == nums[i-1]:
continue
l, r = i + 1, len(nums)-1
while l < r:
sum = nums[i] + nums[l] + nums[r]
if sum > 0:
r -= 1
elif sum < 0:
l += 1
else:
# found three sum
result.append((nums[i], nums[l], nums[r]))
# remove duplicates
while l < r and nums[l] == nums[l+1]:
l + =1
while l < r and nums[r] == nums[r-1]:
r -= 1
l += 1
r -= 1
return result
x = [1, -6, 4, 2, -1, 2, 0, -2, 0 ]
print(three_sum(x))
Output:
[(-6, 2, 4)]