To develop class String defined for it the following methods:
1Copying of lines, having realized the operator =;
2Searching of interline;
3Merging of lines, having realized operators + = and +;
4Equivalence of lines, a set of operators == and! =;
5Definitions of line length;
6Outputintoa stream, <<;
7Input from a stream>>;
8Inserts interline from the necessary position;
9The constructor of copying of a kind X:: X (const X&);
Write the program illustrating the basic methods of class String.