Write a program to find 100 largest numbers out of an array of 1 billion numbers

Question

I recently attended an interview where I was asked \"write a program to find 100 largest numbers out of an array of 1 billion numbers.\"

I was only able to give a br

Answer 1

This question would be answered with N log(100) complexity (instead of N log N) with just one line of C++ code.

 std::vector myvector = ...; // Define your 1 billion numbers. 
                                 // Assumed integer just for concreteness 
 std::partial_sort (myvector.begin(), myvector.begin()+100, myvector.end());

The final answer would be a vector where the first 100 elements are guaranteed to be the 100 biggest numbers of you array while the remaining elements are unordered

C++ STL (standard library) is quite handy for this kind of problems.

Note: I am not saying that this is the optimal solution, but it would have saved your interview.