题解 | #两数之和# -- [python3]

方法1： 两个指针暴力破解

class Solution:
    def twoSum(self , numbers , target ):
        masterIndex = 0
        subIndex = 1
        arrayLen = len(numbers)
        while masterIndex <= arrayLen -2:
            subIndex = masterIndex + 1
            while subIndex <= arrayLen - 1:
                if target == numbers[subIndex] + numbers[masterIndex]:
                    return [masterIndex + 1, subIndex + 1]
                subIndex += 1
            masterIndex += 1

方法2： 字典模仿哈希表

class Solution:
    def twoSum(self , numbers , target ):
        if len(numbers)>1:
            # key 为 数组值，value为数组索引
            hashMap = {}
            for i in range(len(numbers)):
                another = target - numbers[i]
                # 若在哈希表中，返回其值对应的索引
                if another in hashMap:
                    return [hashMap[another]+1, i + 1]
                # 若不在，则加入哈希表中
                else:
                    hashMap[numbers[i]] = i
            return []
        else:
            return []