摘要： We have two special characters. The first character can be represented by one bit 0. The second character can be represented by two bits (10 or 11). N 阅读全文

摘要： Given an array of integers where 1 ≤ a[i] ≤ n (n = size of array), some elements appear twice and others appear once. Find all the elements of [1, n] 阅读全文