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POHow to use iterators in python
 

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  1. POHow to use iterators in python
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    <p>I'm studying Python and I don't understand how to use iterators.</p> <p>I need to write code. In C it'll be like this:</p> <pre><code>list_node *cp = list_of_chars; char dp = '&gt;'; int flag = 0; while (cp != NULL) { if( isdigit(cp-&gt;val) ) { printf("%c",cp-&gt;val); if( cp-&gt;val == '0' ) { cp-&gt;prev-&gt;next = cp-&gt;next; cp-&gt;next-&gt;prev = cp-&gt;prev; } else cp-&gt;val--; } else if( (cp-&gt;val == '&gt;') || (cp-&gt;val == '&lt;') ) { dp = cp-&gt;val; flag = 1; } if( dp == '&gt;' ) cp = cp-&gt;next; else if( dp == '&lt;' ) cp = cp-&gt;prev; else return ERR; if( flag &amp;&amp; ( (cp-&gt;val == '&gt;') || (cp-&gt;val == '&lt;') )) { cp-&gt;prev-&gt;prev-&gt;next = cp; cp-&gt;prev = cp-&gt;prev-&gt;prev; } } </code></pre> <p>Can you help me translate this code to python? I started to write, but have some errors and I not sure, that I understand documentation.</p> <pre><code> ip = {'cp' : iter(program), 'dp' : '&gt;'} flag = 0 while ip['cp'] != []: if ('0' &lt;= ip['cp']) &amp; (ip['cp'] &lt;= '9'): print ip['cp'] if ip['cp'] == '0': ip['cp'] = [] else: ip['cp'] -= 1 elif (ip['cp'] == '&gt;') | (ip['cp'] == '&lt;'): ip['dp'] = ip.['cp'] flag = 1 else: raise NameError('incorrect cp-value') if ip['dp'] == '&gt;': ip['cp'].next() elif ip['dp'] == '&lt;': ip['cp'].prev() else: raise NameError('incorrect dp-value') if flag &amp; ( (ip['cp'] == '&gt;') | (ip['cp'] == '&lt;') ): ip['cp'].prev() ip['cp'] = [] </code></pre> <p>The question is how can I get the value of the iterator without the function next().</p> <p>Examples of python-expert code with advanced uses of iterators would also be nice to see.</p>
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    1. USSam Mussmann
    1. USKirill Golikov
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    1. COTrying to directly translate C to Python is a terrible idea. You need to translate the concept, not the code. Python is a higher level language and doing things the way one would in C, while in Python, will produce horrible, unpythonic code.
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      1. USGareth Latty
    2. COI know C-prog.lang. And think on it. I try to explain what I need to you and use C for it. I can't explain algorithm another way.
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      1. USKirill Golikov
    3. CO@so-olitary Then your issue is you can't define the question well. You need to give us an exact question. Here you are saying *it doesn't work* - that isn't specific enough. What is the error you get? What is the problem?
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