Task

(Given an equal-probability generator of one of the integers 1 to 5
as dice5),   create dice7 that generates a pseudo-random integer from
1 to 7 in equal probability using only dice5 as a source of random
numbers,   and check the distribution for at least one million calls using the function created in   Simple Random Distribution Checker.


Implementation suggestion:
dice7 might call dice5 twice, re-call if four of the 25
combinations are given, otherwise split the other 21 combinations
into 7 groups of three, and return the group index from the rolls.

(Task adapted from an answer here)

package Random_57 is
 
   type Mod_7 is mod 7;
 
   function Random7 return Mod_7;
     -- a "fast" implementation, minimazing the calls to the Random5 generator
   function Simple_Random7 return Mod_7;
     -- a simple implementation
 
end Random_57;