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Performance

1. If there is some block of useless code, the compile is smart enough to ignore it and thus speed up the program.

2. Use the option -O2 to generate optimized code when you are ready to publish your code.

3. Define variables only when needed to avoid the overhead of creating …

Lambda Function

Check [here[(https://github.com/dclong/cearn/tree/master/lambda) for illustrative examples for the following discussions.

1. When capture variables, you can define new variables in the [] of a lambda expression. For example, if a lambda function need the sum of two double variable x and y, you …

1. {} is more powerful than () and thus is preferred over (). You should use always use {} except for a few cases where () is necessary. For example, if you want to create a vector of length 1000, you have to use

   vector<int>(1000);
   

instead of

    vector<int> {1000};

which create a vector …

GSL is an advance C/C++ library that is widely used. To install GSL, you can download the source file and following instruction in the included README and INSTALL document. For Unix/Linux users, the GSL library is often availabe in the repository. For example, you can use the following …

Difference betwen Lvalue and Rvalue Reference

1. Lvalue and Rvalue are terrible names. They are due to historical reasonal but people stuck with these names.

2. A lvalue reference has a name while a rvalue reference has no name, in other words, a lvalue reference is persistent while a rvalue reference is …