Generate sample of 1,000,000 random permutations

Question

I am working with large number of integer permutations. The number of elements in each permutation is K. The element size is 1 byte. I need to generate N unique random permu

Answer 1

Heres one way of doing it.

1) generate first N permutations and store them on the disk.

2) then run a randomize algorithm on the permutations.

You can optimize using Divide and Conquer , by picking only a first X elements from the disk and then randomizing it, and the next X elements in the next iteration, and so on... and then merge the results.

You probably don't need the disk here.