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问题描述： You are climbing a stair case. It takes n steps to reach to the top. Each time you can either climb 1 or 2 steps. In how many distinct ways can 阅读全文
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问题描述： Given an array of numbers nums, in which exactly two elements appear only once and all the other elements appear exactly twice. Find the two ele 阅读全文
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问题描述： Given an array of integers, every element appears three times except for one. Find that single one. Note:Your algorithm should have a linear run 阅读全文
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问题描述： Given an array of integers, every element appears twice except for one. Find that single one. Note:Your algorithm should have a linear runtime c 阅读全文