making different numbers with same digits

hello,

how do I make sure to find the next number greater and less than the number requested from the user, but it must contain the same digits as the requested number

for exemple: you get 536 so the answer will be 365 and 635

Answer 1

[Image Analyst]

Try this:

% Create original number
nUser = 536;
% Convert to string.
strx = num2str(nUser);
% Get all possible permutations of the digits.
p = perms(1 : length(strx))
% Make list of all possible combinations
counter = 1;
for k = 1 : size(p, 1)
	nAll(k) = str2double(strx(p(k,:)));
end
% Sort them
nSorted = sort(nAll, 'ascend');
% Find the index of the original number
index = find(nSorted == nUser)
% Get the two numbers that are just below and just above that number.
n = [nSorted(index-1), nSorted(index+1)];
% All Done!  Display all the numbers in the command window:
nAll
n

You'll see

p =

3 2 1

3 1 2

2 3 1

2 1 3

1 3 2

1 2 3

index =

3

nAll =

635 653 365 356 563 536

n =

365 563

n is a list of all possible numbers that can be created from your original digits.

Be aware that you'll have to do some validation to see if the user's number is the smallest or largest possible because there would be no lower or higher number in those cases.

Is this what you were looking for?

[Jens Petit-jean]

hello,

thanks that was what I was looking for but how can I make sure that some numbers don't repeat

for exemple 366 because there are two 6 each number will repeat 2 times

[Image Analyst]

Check the input string for that before you get very far:

% Create original number
nUser = 366;
% Convert to string.
strx = num2str(nUser);
% See if any digits repeat
for k = 1 : length(strx)
	numOccurrences = sum(strx == strx(k));
	if numOccurrences > 1
		% There is a repeat.  Warn the user.
		errorMessage = sprintf('Error : %s occurs %d times in %s.\nEach digit must appear only once',...
			strx(k), numOccurrences, strx);
		uiwait(errordlg(errorMessage));
		% Bail out of the program.
		return;
	end
end
% Get all possible permutations of the digits.
p = perms(1 : length(strx))
% Make list of all possible combinations
counter = 1;
for k = 1 : size(p, 1)
	nAll(k) = str2double(strx(p(k,:)));
end
% Sort them
nSorted = sort(nAll, 'ascend');
% Find the index of the original number
index = find(nSorted == nUser)
% Get the two numbers that are just below and just above that number.
n = [nSorted(index-1), nSorted(index+1)];
% All Done!  Display all the numbers in the command window:
nAll
n

[Jens Petit-jean]

thanks but now you get a error message when a number is double but is therre a possibillty to just don't hav the numbers double

for exemple the number 366

366

366

636

636

663

663

but I just need it like this:

366

636

663

Thanks in advance!

[Image Analyst]

After you get nAll, pass it through unique():

nAll = unique(nAll);

[Jens Petit-jean]

thanks!!!

Answer 2

[Ameer Hamza]

Try this

x = 536;
y = num2str(x);
idx1 = randi([2 numel(y)]); % to make sure we don't get same number
idx = [idx1 setdiff(randperm(numel(y)), idx1)];
y = str2double(y(idx));