Using namespace std in Dev C++

Using namespace std :

Its clear from the above that the phase is having three words:-

using- means using what??

namespace - means using a namespace

Std - it is a kind of namespace

Therefore, the phase defines using a namespace of kind std.

Why to use it ??

The built in C++ library routine are kept in the standard namespace. That includes stuff like cout, cin, string, vector, map etc. Because these tools are used so commonly, it's popular to add" using namespace std " at the top of your code source code so that you won't have have to type the std:: prefix contantly before cout, cin etc.

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