Given an array of integers, return indices of the two numbers such that they add up to a specific target.

You may assume that each input would have exactly one solution.


Given nums = [2, 7, 11, 15], target = 9,

Because nums[0] + nums[1] = 2 + 7 = 9,
return [0, 1].

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Pluto surrounded by a blue haze

latest Pluto image

和地球不同,冥王星上既没有厚厚的大气层,也没有海洋,所以 NASA 认为它更多是气雾。

据 NASA 研究员 Carly Howett 介绍,冥王星的大气成分主要是氮和甲烷,它们在太阳照射的情况下会分解成一种叫 tholins 的粒子,正是这些粒子的堆积才造成了这种景象。

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