title: does namespace inclusion increases size of exe
body: <p>I attended a session in which it was taught that we should not use &quot;using namespace std&quot;, instead do &quot;std::cout&quot; for using some call of the std namespace as <em><strong>this shall increase size of the binary</strong></em></p>
  <p>I tried verifying the same with the following experiment. The code &amp; its output is as follows:-</p>
  <pre><code>    [Fooo@EXP]$ cat namespacestd.cpp
      #include&lt;iostream&gt;
  
      #ifdef STD
              using namespace std;
      #endif
  
      int main()
      {
      #ifndef STD
              std::cout&lt;&lt;&quot;\n ==&gt; Workign \n&quot;;
      #else
              cout&lt;&lt;&quot;\n ==&gt; Workign \n&quot;;
      #endif
  
      return 0;
  
      }
  
  
      [Fooo@EXP]$ time g++ -c namespacestd.cpp -DSTD
  
      real    0m0.246s
      user    0m0.215s
      sys     0m0.030s
      [Fooo@EXP]$ size namespacestd.o
         text    data     bss     dec     hex filename
          310       8       1     319     13f namespacestd.o  
      [Fooo@EXP]$ time g++ -c namespacestd.cpp
  
      real    0m0.258s
      user    0m0.224s
      sys     0m0.034s
      [Fooo@EXP]$ size namespacestd.o
         text    data     bss     dec     hex filename
          310       8       1     319     13f namespacestd.o
  
      [Fooo@EXP]$ time g++ -o namespacestd namespacestd.cpp -DSTD
  
      real    0m0.293s
      user    0m0.251s
      sys     0m0.042s
      [Fooo@EXP]$ size namespacestd
         text    data     bss     dec     hex filename
         1980     580     288    2848     b20 namespacestd
      [Fooo@EXP]$ time g++ -o namespacestd namespacestd.cpp
  
      real    0m0.274s
      user    0m0.239s
      sys     0m0.035s
      [Fooo@EXP]$ size namespacestd
         text    data     bss     dec     hex filename
         1980     580     288    2848     b20 namespacestd
      [Fooo@EXP]$
  </code></pre>
  <p>As I see from my experiment that</p>
  <p><em><strong>there is no effect on the size of binary</strong></em></p>
  <p>only</p>
  <p><strong>there is a difference in the compilation time</strong>.</p>
  <p>Kindly correct me if my conclusions are flawed</p>
  <p>Thanks</p>