array 1 

from typing import List
lis = ["a","b", "c", "d"]

# for i in lis:
#    print(i)

print(lis[2])
lis.append("e")
lis.pop()
lis.pop()

lis.insert(0, 'x')
# lis.insert(len(lis), 't')
lis[3:3] = ['alien']
# lis.splice(2, 0, "alien")
print(lis)
print()
def threeSum(nums: List[int]) -> List[List[int]]:
    total = len(nums)
    count = 0
    for i, n in enumerate(nums):
        print(i, n)
        if (n + n[i + 1]):
            ...
    if total:
        return total
    else:
        return []
           
           
input = [-1,0,1,2,-1,-4]
result = threeSum(input)
print(result)