Project Euler has about 700 problems, but the current repository hosts solutions for only about 60-70 problems.
I'm willing to work on the issue and also if someone wants to help they can join in.
We can create guidelines on how many minimum solutions a PR should have to prevent spammy PRs with just one or two easy solutions. (open to discussion)

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To begin contributing, you shall get a quick overview of how Cosmos is used today. Cosmos is one of the most extensive code database and is used as:

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Add quickselect algorithm. Quickselect is a selection algorithm to find the kth smallest element in an unordered list.

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• Add more algorithms #14 #195

thank you

steps to reproduce

Write a loop, from 1 to 80000, each time add a random int to the max heap.

In theory it takes very little time(NlogN, N=80000, <1sec ), but the program does take a long time.

I'v also tested the BinaryHeap in https://github.com/SolutionsDesign/Algorithmia, it performs well, so it is probably due to the bad algorithm.