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info planetizer
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By brute forcing you get to be familiarize with the problem better. A common theme for brute forcing means you are going to have a for loop inside a foor loop something like the below, so it's great to get familiarize with common bruteforcing snippets, example:

// Brute force find all continuous subsequences.

for (int startIndex = 0; startIndex < arr.length; startIndex++) {

for (int Index = 0; endIndex < arr.length; endIndex++) {

for (int i = startIndex; i++; i < endIndex) {

System.out.println(arr[i]); time complexity O(n^3) as we have loops nest.

}

}

}

No idea how to brute force? imagine you have more memory space, use an additional hashmap to help you. Sometimes the answer even relies on that on additional space, if you could solve it this way, again, say the time and space complexity and ask if to reduce the space complexity, if yes continue with next steps.

Sometimes if you just sort the input or apply a transformation to it, the problem is easily solved, so try to sort it at first, see if it helps. (this might not be the final answer but it can take you a step further).

Start thinking of the different data structures you know, **hashmap**, **set**, .. if you could apply them to the data in the problem or use their help would it help?

Left, right = split(input) // first split can be in sort body

sort(left) // call self with left

sort(right) // call self with right

merge(left, right) // create new merge method.

Use slow and fast pointers, fast moves node.next.next! then when fast get's to the end of the list this means your slow pointer is at the middle of the linked list!

Get familiarize with coding snippets which are extremely useful for interviews. See: http://www.programcreek.com/2012/11/top-10-algorithms-for-coding-interview/

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Veri nicely explained, thanks for sharing.

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