[SOLVED] CS590 homework 1 – C++ & running times

You are given an integer vector which is represented by int* an array of integers and its dimension m as a
separate parameter. We are interested in sorting arrays of integer vectors according to a pre-defined
notion of vector length. You therefore are given the function ivector_length(v, m) that computes and
returns the length of vector v with dimension m as
You are given a naive (and very inefficient) implementation of insertion sort for arrays of integer vectors.
Questions (100 points)
1. Develop an improved implementation of insertion sort for integer vector (insertion_sort_im) that
precomputes the length of each vector before the sorting. Keep in mind that the vectors are sorted
according to their length (see ivector_length function). You can test the correctness of your sorting
algorithm using the provided check_sorted function.
2. Implement a merge sort for an array of integer vectors. As for the improved insertion sort algorithm,
you should precompute the length of the vectors before the sorting and the sorting is done according to
the vector length. Test the correctness of your merge sort implementation using the provided
check_sorted function.
3. Measure the runtime performance of insertion sort (naive and improved) and merge sort for random,
sorted, and inverse sorted inputs of size n = 10000; 25000; 50000; 100000; 250000; 500000; 1000000;
2500000 and vector dimension m = 10; 25; 50. You can use the provided functions create_random_ivector,
create_sorted_ivector, create reverse_sorted_ivector.
Repeat each test a number of times (usually at least 10 times) and compute the average running time for
each combination of algorithm, input, and size n. Report and comment on your results.
Remarks:
• You might have to adjust the value for n depending on your computers speed, but allow each test
to take up to a couple of minutes.
• Start with smaller values of n and m and stop if one instance of the algorithm takes more than 10
min to complete (the insertion sort implementations will hit that limit early on).
• Report and comment means that you have to analyze and interpret your findings properly. What
do the experiments tell you?
• The programming, testing and the experimentation will take some time. Start early.
• Feel free to use the provided source code for your implementation. You have to document your
code