Problem 722. Make a run-length companion vector
Given a vector x, return a vector r that indicates the run length of any value in x. Each element in r shows how many times the corresponding element in x has appeared consecutively.
Example:
Input x = [5 3 3 1 0 9 9 4 4 4 4 5 1 2 2] Output r = [1 1 2 1 1 1 2 1 2 3 4 1 1 1 2]
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6 Comments
The first test case seems to be invalid answer. Please check it
Hi Wenwu: Could you be more specific about what you think the problem is?
See FileExchange's seqle . (disclaimer: I'm the author)
False exemple description
y=[];
for i = 1:length(delta)
test = max(delta(1:i));
maxsofar=max(delta(1:i-1));
test2=min(delta(1:i));
minsofar=min(delta(1:i-1));
if test == delta(i) && delta(i)~= maxsofar
y=[y,1];
elseif test2 == delta(i) && delta(i)~= minsofar
y=[y,-1];
else
y=[y,0];
end
end
this code despite its giving correct results it is rejected by the tests...
There are reasonable situations that are not addressed by the problem definition or tested for.
IE if there was a case such as x = [5 3 3 1 3 3 3] is the expected answer
r = [1 1 2 1 1 2 3] or
r = [1 1 2 1 2 2 3]?
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