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I've never walked into the following problem with iterators, so I really do not know where the solution might start. I have a LIST "StringOfPearls" which is permuted right before I do the following:

DNAr = StringOfPearls->begin(); // Added 1 element to the beginning of this list in earlier line of code
cout << "pos DNAr before bumping by 1: " << distance(DNAreplicase, StringOfPearls->begin()) << endl;
advance(DNAreplicase, 1);
cout << "pos DNAr after bumping by 1: " << distance(DNAreplicase, StringOfPearls->begin()) << endl;

Returns:

pos DNAr before bumping by 1: 0
pos DNAr after bumping by 1: 10

No doubt I'm just missing something silly, but can anyone help me out?

Brem
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1 Answers1

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You are not using std::distance correctly. begin iterator is the first argument, e.g. 

distance(StringOfPearls->begin(), DNAreplicase)

This is the convention for all functions taking pairs of iterators denoting a range.

Maxim Egorushkin
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    Update for C++11: _"The value may be negative if random-access iterators are used and first is reachable from last."_ source: http://en.cppreference.com/w/cpp/iterator/distance – Richard Critten Sep 19 '17 at 10:33