I have used divide and conquer, as we seen before, to recursively break it into smaller problems. But the smaller problem of fib of 4 and the smaller problem of fib of 3 overlap with each other.

正如我们之前看到的，我已经进行了划分,并且递归性的把它分解为更小的问题,但是fib的简化问题,和fib的简化问题会相互重叠。

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