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Given a robot cleaner in a room modeled as a grid.Each cell in the grid can be empty or blocked.The robot cleaner with 4 given APIs can move forward, 阅读全文
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Given a linked list and a value x, partition it such that all nodes less than x come before nodes greater than or equal to x.You should preserve the o 阅读全文
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Given a sorted array of integers nums and integer values a, b and c. Apply a quadratic function of the form f(x) = ax2 + bx + c to each element x in t 阅读全文
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Given a C++ program, remove comments from it. The program source is an array where source[i] is the i-th line of the source code. This represents the 阅读全文
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You are given a list of non-negative integers, a1, a2, ..., an, and a target, S. Now you have 2 symbols + and -. For each integer, you should choose o 阅读全文