What does include iostream do

Asked 7 years, 7 months ago. Active 1 month ago. Viewed k times. Is it required every time as a heading? Improve this question. William William 1 1 gold badge 3 3 silver badges 7 7 bronze badges. What exactly is the stream? Add a comment. Active Oldest Votes. Improve this answer. Elliott Frisch Elliott Frisch k 19 19 gold badges silver badges bronze badges. Ramzan Ramzan 1 1 silver badge 10 10 bronze badges.

Files specified by include are transcluded at the point of the include , not the start of the file — CSM. Sign up or log in Sign up using Google. Suppose if you have a function called max and there is another library available which also having some function max.

Now compiler has no way of knowing which max function. Now compiler has no way of knowing which max function you are referring to within your code. A namespace is defined to overcome this difficulty and is used as additional information to differentiate similar functions, classes, variables etc. In essence, a namespace defines a scope.

If you don't write using namespace std; and the compiler sees the string or vector it will not know what you are referring to. You will need to explicitly tell it std::string or std::vector , and if you don't, you will get a compile error. There are various header files libraries which are standard and are already present in the directories. What does is to specify that the command is to be handled by a preprocessor and not during compiler time. It again tells the compiler to include the header file conio console input output.

This is not a standard header, and is not present in all of the compilers. File Handling. Table of Contents. Save Article. Improve Article. Like Article. Recommended Articles. Article Contributed By :.

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