Coupon Collector's Test

We use the sequence Y0, Y1, Y2, ,,,, produced by the random number generator and observe the lengths of segments Y[j+1], Y[j+2] ,,, and Y[j+r] that are required to get a complete set of integers from 0 to d - 1. d is chose to be 256 for this version. The function returns a uniform random no. in [0,1]. The test is failed if the value less than 0.001 or larger than 0.999.