How can I solve this odd/even loop question (hailstone sequence)?

4 次查看（过去 30 天）
mrs_matlab_rookie_thanks
编辑： Walter Roberson 2015-9-22
n = 71
If n is even, divide it by 2 to get n / 2.
If n is odd, multiply it by 3 and add 1 to obtain 3n + 1.
Repeat process until n = 1.
I need to find out how many steps it takes to reach 1..
thanks!
  2 个评论
mrs_matlab_rookie_thanks
mrs_matlab_rookie_thanks 2015-9-22
ok, so im really new to matlab, but this is what i tried doing:
n(1,1) = 71;
iterations(1,1) = 0;
ii=1;
while n(1,ii)==1;
if mod(n(1,ii),2)==1
(3*n(1,ii))+1;
else n(1,ii)/2;
ii=ii+1;
end
iterations(1,ii) = iterations(1,ii) + 1;
end

请先登录，再进行评论。

请先登录，再回答此问题。

采纳的回答

Varun Pai
Varun Pai 2015-9-22
I think this is your requiremnt. Please check
num = 71;
count = 0;
while(num~=1)
count = count+1;
if(mod(num,2)==0)
num = num/2;
else
num = 3*num + 1;
end
end
fprintf('count = %d', count);

更多回答（1 个）

Thorsten
Thorsten 2015-9-22
First you can skip the 1, and just write n(ii).
Next you have forgotten to assign the new value, and you have to move the increment of ii outside the else-clause
if mod(n(ii),2)==1
n(ii+1) = 3*n(ii)+1;
else
n(ii+1) = n(ii)/2;
end
ii=ii+1;
Finally you have to change the while loop condition; while n(ii) == 1 means that the loops only continues if the n is 1, but it should continue if n is NOT 1.

类别

在 Help Center 和 File Exchange 中查找有关 Programming 的更多信息

标签

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by