String Stream Operators
Syntax:
  #include <sstream>
  operator<<
  operator>>

Like C++ I/O Streams, the simplest way to use string streams is to take advantage of the overloaded << and >> operators.

The << operator inserts data into the stream. For example:

  stream1 << "hello" << i;

This example inserts the string "hello" and the variable i into stream1. In contrast, the >> operator extracts data out of a string stream:

  stream1 >> i;

This code reads a value from stream1 and assigns the variable i that value.