Hamming's Problem: (Applet)

Given a list P of prime numbers in increasing order, output a
list L of integers, in increasing order, such that for every
integer X in L, all the prime factors of X
are members of P and every integer not in L has at
least one prime factor that is not in P.
Example:
If P = { 3,5,11 }
Then L = { 3,5,9,11,15,25,27,33,45,55,...}

  

slowham.c

Generate and test solution to Hamming's problem (very slow).


Stream.java

Threaded Stream class, used by S1.java and Hamming_0.java.


S1.java

Data driven solution to Hamming's problem, in Java, with Threads.


Hamming_0.java

Alternative to the above, slightly improved.


hamming.cc

A C++ data driven solution without Threads using classes as closures.


bigint.cc

Homemade BigInteger support for hamming.cc.


bigint.h

Include file for bigint.cc and hamming.cc.


Makefile

Makefile for hamming.cc, bigint.cc, bigint.h.


StreamC.java

Unthreaded Stream class for use by Hamming_1.java and Hamming_2.java.


BIArrayC.java

Big Integer array class used by Hamming_1.java and Hamming_2.java.


Hamming_1.java

Java data driven solution mimicking hamming.cc (no Threads).


Hamming_2.java

An application version of the above.


hamming.hs

Haskell data driven solution (uses streams)

Topological Sort

Given a set N of Nodes, each having a dependency set
M of Nodes which is a subset of N. Find a linear
order L for the Nodes of N such that every Node exists
in L after all nodes in its dependency list
M. Such a linear order is called a topological sort
of the partial order described by the Nodes and their dependency sets.
Example:
If N = {1,2,3,4}
and M(1) = {2,4}, M(2) = {4}, M(3) = {1},
M(4) = {}
Then L = [4,2,1,3].

Stirling Numbers:

Stirling numbers are defined recursively as follows:
S(m,n) = S(m1,n1) + m*S(m,n1);
S(0,n) = 0;
S(1,n) = 1;
S(n,n) = 1;
Example:
S(1,10)=1, S(2,10)=511, S(3,10)=9330, S(4,10)=34105, S(5,10)=42525

Fibonacci Numbers:

Fibonacci numbers are defined recursively as follows:
F(n) = F(n1) + F(n2);
F(0) = 1;
F(1) = 1;
Example:
F(2)=2, F(3)=3, F(4)=5, F(5)=8, F(6)=13

  

Fibon.java

Data driven Java solution with Threads.

