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POstringstream not working as expected
 

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    <p>I am trying to write program for parsing and processing text file. After not being successful with implementing <strong>sscanf</strong> i decided to try <strong>stringstream</strong>.</p> <p>I have vector of strings containing data separated by spaces, like:</p> <blockquote> <p>some_string another_string yet_another_string VARIABLE_STRING_NO_1 next_string</p> </blockquote> <p>I wrote code and expected result would be:</p> <pre><code>Counter: 4 Variable number 1 : VARIABLE_STRING_NO_1 Variable number 2 : VARIABLE_STRING_NO_2 Variable number 3 : VARIABLE_STRING_NO_3 Variable number 4 : VARIABLE_STRING_NO_4 </code></pre> <p>but instead i get:</p> <pre><code>Counter: 4 Variable number 1 : VARIABLE_STRING_NO_1 Variable number 2 : VARIABLE_STRING_NO_1 Variable number 3 : VARIABLE_STRING_NO_1 Variable number 4 : VARIABLE_STRING_NO_1 </code></pre> <p>Can anyone push me in right direction please? (eg. use other container instead of vector, change method to... etc)</p> <p>Also what if <strong>VARIABLE_STRING</strong> contains 2 sub-strings with space inbetween? That is possible in my data.</p> <p>Sample code:</p> <pre><code>#include &lt;iostream&gt; #include &lt;sstream&gt; #include &lt;vector&gt; using namespace std; int main() { vector&lt;string&gt; vectorOfLines, vectorOfData; vectorOfLines.push_back("some_string another_string yet_another_string VARIABLE_STRING_NO_1 next_string"); vectorOfLines.push_back("some_string another_string yet_another_string VARIABLE_STRING_NO_2 next_string"); vectorOfLines.push_back("some_string another_string yet_another_string VARIABLE_STRING_NO_3 next_string"); vectorOfLines.push_back("some_string another_string yet_another_string VARIABLE_STRING_NO_4 next_string"); string data = "", trash = ""; stringstream token; int counter = 0; for( int i = 0; i &lt; (int)vectorOfLines.size(); i++ ) { token &lt;&lt; vectorOfLines.at(i); token &gt;&gt; trash &gt;&gt; trash &gt;&gt; trash &gt;&gt; data &gt;&gt; trash; vectorOfData.push_back(data); // wrong method here? counter++; // counter to test if for iterates expected times } cout &lt;&lt; "Counter: " &lt;&lt; counter &lt;&lt; endl; for( int i = 0; i &lt; (int)vectorOfData.size(); i++ ) { cout &lt;&lt; "Variable number " &lt;&lt; i + 1 &lt;&lt; " : " &lt;&lt; vectorOfData.at(i) &lt;&lt; endl; } return 0; } </code></pre> <p>Excuse my newbie question but after trying different approaches for last 5 days, I got to the point of swearing and getting discourages to continue learning.<br> Yes I'm very new to C++.<br> I've successfully done the same program in PHP (being total newbie in that too) and it seems like C++ is much, much harder to do.</p>
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    1. USRegEx
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    1. COwhat is the goal of `token >> trash >> trash >> trash >> data >> trash;`?
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      1. USBostonJohn
    2. COBy the way, printing `vectorOfLines.at(i)` before inserting into `token` yields correct results and printing `token.str()` right after inserting the line always yields the first line.
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      1. USchris
    3. COYou need to check the >> operator is succeeding, otherwise you're using the old value of the string from the previous iteration.
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      1. USFlexo
 

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