/ftl-pseudorandom-generator

Primary LanguageC++

Workshop on Pseudorandom Number Generator in FTL

What does it do

This program receives as input the numbers A, B, C, D, seed_1, seed_2, seed_3, which set the generator of pseudorandom numbers by the recursive formula $$x[seed] = (A * x[seed - 3] + B * x[seed - 2] + C * x[seed - 1]) \% D$$ and finds the following parameters of this generator:

  • period
  • pre-period
  • its estimated characteristic Z, which is calculated as follows:
    • using the generator, we obtain 400 pseudorandom numbers
    • normalize these numbers (bring them to the half-interval [0, 1))
    • divide the numbers into 20 equal segments [0, 1/20), [1/20, 2/20), ..., [19/20, 20/20) and count how many numbers are in each (let's call this distribution arr, where arr[i] is the number of numbers in the segment [i/20, (i + 1) / 20).
    • calculate Z by the formula $$Z=\sum_{i=1}^{20} \frac{(arr_i-20)^2}{20^2}$$

Launch

$ g++ main.cpp -o main.o -I.

Note: we need "-I." to include local file debug.h.

Testing

$ python3 tests/tester.py
Building...
Done.
Testing subgroup 'main_tests'...
1 OK
.2 OK
.3 OK
.4 OK
.5 OK
.6 OK
.
----------------------------------------------------------------------
Ran 6 tests in 0.001s

OK