#導入計算時間的包，調用系統(tǒng)時間
from time import * 
#初始時間
t1 = time()
def threeSum(nums):
    nums.sort()
    n = len(nums)
    res = []
    for i in range(n):
        '''如果相鄰的兩個數(shù)相等，跳過,避免重復'''
        if i > 0 and nums[i] == nums[i-1]:
            continue 
        l, r = i+1, n-1
        while l < r:
            if nums[i] + nums[l] + nums[r]>0:
                r -= 1
                while nums[r+1] == nums[r]:
                    r -= 1
            elif nums[i] + nums[l] + nums[r]<0:
                l += 1
                while nums[l-1] == nums[l]:
                    l += 1    
            else:
                res.append([nums[i],nums[l],nums[r]])
                l += 1
                r -= 1
                while nums[l] == nums[l - 1]: l += 1
                while nums[r] == nums[r + 1]: r -= 1
    return res
        
if __name__ == '__main__':
    nums = [-1,0,1,2,-1,-4]
    print(threeSum(nums))
#結束時間
t2 = time()
#運行時間
run_time = t2 - t1
print(run_time)

運行結果：

[[-1, -1, 2], [-1, 0, 1]]
#運行時間
0.0010113716125488281

以上代碼有一些思想錯誤：

遺漏了如果三個數(shù)全部大于0，則退出循環(huán)，因為沒有滿足條件的結果。

沒有嚴格判斷每一次的l<r的條件。

修正后的代碼：

from time import * 
t1 = time()
def threeSum(nums):
    nums.sort()
    n = len(nums)
    res = []
    for i in range(n-2):
        if nums[i] > 0:break
        '''如果相鄰的兩個數(shù)相等，跳過,避免重復'''
        if i > 0 and nums[i] == nums[i-1]:
            continue 
        l, r = i+1, n-1
        while l < r:
            if nums[i] + nums[l] + nums[r]>0:
                r -= 1
                while l < r and nums[r-1] == nums[r]:
                    r -= 1
            elif nums[i] + nums[l] + nums[r]<0:
                l += 1
                while l < r and nums[l] == nums[l-1]:
                    l += 1    
            else:
                res.append([nums[i],nums[l],nums[r]])
                l += 1
                r -= 1
                while l < r and nums[l] == nums[l - 1]: l += 1
                while l < r and nums[r] == nums[r + 1]: r -= 1
    return res
        
if __name__ == '__main__':
    nums = [-2,-3,0,0,-2]
    print(threeSum(nums))
t2 = time()
run_time = t2 - t1
print(run_time)

結果：