Nested While and If Loops

Hi

The code I wrote is supposed to do the following for a given array containing numbers:

- Prompt the user to enter a number, compare it to array(1). If they do not match, increase a given initialspeed - If they do match, prompt the user for the next number: If it does not match array(2) - increase initialspeed. If they do match - prompt the user for the third input - if it does match array(3), now decrease initialSpeed. If they do not match, again increase.

I have coded it as follows, however would like to know if there is a more efficient way to code it? Also, it seems that I get prompted for an input even when the length of the initial array is exceeded - why is that?

initialspeed = 300;
sequenceArray = [12345,54321,12435,51234,42315] % compare the input to this array
k = 1 % loop variable
sequence = zeros(1,length(sequenceArray)) % store the input here

while k < length(sequenceArray)+1

prompt = 'Type in participants answer:';
sequence(k) = input(prompt);

if  sequence(k) ~= sequenceArray(k)
    initialspeed = initialspeed + 50;
    disp(initialspeed)
    k = k+1;
else
    k = k+1;
    prompt = 'Type in participants answer:';
    sequence(k) = input(prompt);

      if sequence(k) ~= sequenceArray(k)
          initialspeed = initialspeed + 50;
          disp(initialspeed)
          k = k+1;

      else 
          k = k+1;
          prompt = 'Type in participants answer:';
          sequence(k) = input(prompt);

      if  sequence(k) ~= sequenceArray(k)
          initialspeed = initialspeed + 50;
          disp(initialspeed)
          k = k+1;

      else
          initialspeed = initialspeed - 40;
          disp(initialspeed)
          k = k+1;

      end
  end
  end
  end

Answer 1

[Jan]

Some code indentation and moving common code outside the IF branches:

initialspeed  = 300;
sequenceArray = [12345,54321,12435,51234,42315]; % compare the input to this array
k             = 1; % loop variable
sequence      = zeros(1,length(sequenceArray)); % store the input here
prompt        = 'Type in participants answer:';

while k < length(sequenceArray)+1
   sequence(k) = input(prompt);

     if sequence(k) ~= sequenceArray(k)
        initialspeed = initialspeed + 50;
     else
        k           = k+1;
        sequence(k) = input(prompt);

        if sequence(k) ~= sequenceArray(k)
           initialspeed = initialspeed + 50;
        else
           k           = k+1;
           sequence(k) = input(prompt);

           if sequence(k) ~= sequenceArray(k)
              initialspeed = initialspeed + 50;
           else
              initialspeed = initialspeed - 40;
           end
        end
     end
     disp(initialspeed)
     k = k+1;
  end

You are prompted for further inputs even if the length is actually reached, because there are up to 3 input commands inside the loop.

The intention of the code is hard to recognize. I boldly guess, that you want something else, most of all because you are surprised, when the prompts appear more often than you expect.