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    <p>As a solution to my comment above, the C++ version of the code you presented:</p> <pre><code>typedef map&lt;std::string, int&gt; wc; int main() { int c; string cc, nombre; wc m; std::cin &gt;&gt; c; while (c--) { std::cin &gt;&gt; cc; std::getline(std::cin, nombre); m[cc] += 1; // This should work } printmap(m); } </code></pre> <p><a href="http://ideone.com/2JP82" rel="nofollow">http://ideone.com/2JP82</a></p> <p>First: <code>std::map</code> sorts it's data based on the key, in your code, <code>char*</code>, which points at <code>char cc[75]</code>. So when you replaced the text in <code>cc</code>, then the keys of the map changed, and that breaks everything. The keys of a map <em>must not change ever</em>. Since we're using C++, you should not use <code>char[]</code> at all; use <code>std::string</code> instead, which (since it is a "value type") will make everything just magically work. I have no idea how it was working before, since you don't show the <code>printmap</code> function.</p> <p>Second: You call <code>printmap</code> each and every time you read a single line, and since a <code>map</code> has no way of printing "the last thing added", that idea makes no sense at all. The <code>printmap</code> call should probably print the entire map, and be outside the loop.</p> <p>Third: Don't use <code>scanf</code>, it's not safe. Use streams: <code>std::cin &gt;&gt; cc</code> for reading in a single word, or <code>std::getline(std::cin, nombre)</code> for reading in what's left on the line. That way the code won't crash if someone enters the line (sources for <a href="http://www.funtrivia.com/askft/Question33835.html" rel="nofollow">longest country name</a> and <a href="http://answers.yahoo.com/question/index?qid=20081022055524AAXVIOc" rel="nofollow">longest last name</a>)</p> <pre><code>Krungthepmahanakornamornratanakosinmahintarayuttha-yamahadilokphopnopparatrajathaniburiromudomrajaniw-esmahasatharnamornphimarnavatarnsathitsakkattiyavi-sanukamprasit Wolfeschlegelsteinhausenbergerdorffvortschaferswesenchafewarenwholgepflegeunzenvonangereifenduchihrraubgiriigfeindtausendjahresvorandieerscheinenbanderechiffgebrauchlichtalsseinursprungvonkrrthinzwischensternartigraumaufdersuchebtbewohnbarplanetenkreisedrehensichundstandigmenshlichkeittkonntevortpflanzeslamdlichfreudeundruhemitnichteinfurchrintlligentgeschopfsvonhinzwischenster </code></pre>
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    1. CO+1 for @MooingDuck's edit. >_>
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    2. COAlthough the way the OP uses `scanf` is indeed unsafe, I would not agree that `scanf` is not safe *in general*. Following a very simple rule that the format specifier must provide the limit on the string fixes the safety issue, making the function usable when you prefer C-style I/O (which is also a first-class member of the C++ standard library).
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    3. COMost C++ programmers agree that streams are better than `scanf`, for type safety alone.
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