clear;
enc = 'rbuxd';
oenc = unique(enc);%ordered enc with no duplicates
y = double(oenc)-96;	%array of the codomain, with letters as alphabetic values
% string length of oenc = array size of y
length = numel(oenc);


%consider if there are only advances
alladvances=[];
alladvancesstr='a';
if y(1)~=1
	for a = 1:length
		alladvances(a) = y(a)- a;	%shifting back 'a' places
	end;
end;

for a =1:numel(alladvances)
	alladvancesstr(a)=char(alladvances(a)+96);
end;
clc;
alladvancesstr


%% number of wraps = size of codomain, n, of first letters of alphabet, which are common to codomain.
%% eg if codomain has size = 5, then the number of possible wraps = number of letters which are in codomain
%% and first 5 letters of alphabet

numwraps = 0;
for a = 1:length	%working out how # of possible wraps = numwraps
	if (y(a)>= 1 & y(a)<= length)
		numwraps=numwraps+1;
	end;
end;
numwraps

wraps=[];
for a = 1:numwraps
	wraps(a)=y(a);	%% this finds which letters (as alphabetic numbers though) could be wraps
end;
wraps

%need to consider number of wraps from 1 to numwraps
%start at 1, then do 2 or 3 and generalise

% considering only 1 wrap here, so could be 1st wraps, 2nd wraps, 3rd wraps,..., numwraps wraps
% consider 1st letter wraps - what are the limits of a wrap?



%%then consider 2 wraps
%%1st & 2nd, 1st & 3rd,...,1st & numwraps; then 2nd & 3rd, 2nd & 4th,...,2nd &numwraps;...;numwraps-1 and numwraps

%%consider 3 wraps
%% 1st 2nd 3rd, 124, 125,...,12numwraps;134,135,...,13numwraps;...;1(numwraps-1)numwraps. 234,235,...,23numwraps; 245,246,...,24numwraps;...,2(numwraps-1)numwraps......(numwraps-2)(numwraps-1)(numwraps)




%%need to substitute letters in enc to find the possible plaintexts