Day1

python：

def twoSum(nums, target):
    lens = len(nums)
    j=-1
    for i in range(lens):
        if (target - nums[i]) in nums:
            if (nums.count(target - nums[i]) == 1)&(target - nums[i] == nums[i]):#如果num2=num1,且nums中只出现了一次，说明找到是num1本身。
                continue
            else:
                j = nums.index(target - nums[i],i+1) #index(x,i+1)是从num1后的序列后找num2                
                break
    if j>0:
        return [i,j]
    else:
        return []

来源：CSDN

作者：超爱小橘

链接：https://blog.csdn.net/Zenobia_zzz/article/details/104599874