Rule of 'Maximal Munch'
This rule is also called the 'Greedy Technique', which is used by the lexical analyzer of a C/C++ Compiler. This rule tells us how to evaluate tokens in C/C++. For example consider the following statement.
int x=20, y=10, z;
What is the Output? One possible Output is obtained by considering the statement as z = x- -y; In that case the Output is 30. But if you compile the code, you will get a syntax error. The rule of 'Maximal Munch' has played a role here. C/C++ lexical analyzer always identifies the largest possible token from a given statement. So the above statement is read by the lexical analyzer as z=x-- y; So instead of recognizing the Minus operator (-) followed by the Unary Minus operator (-), a Unary Decrement operator (--) is recognized by the C/C++ lexical analyzer. Thus the statement shows a syntax error because of the missing semicolon after the Unary Decrement operator.
Now Consider the following Statements.
Which of them works and which of them shows an error ?
If you didn't get the answer, please select the red text area given below using your mouse to view the answer.
1. z=x++y; Shows a Syntax Error because it is taken as
z=x++ y; by the Compiler.
2. z=x+++y; Shows the Output as 30 because it is taken as
z=x++ +y; by the Compiler.
3. z=x++++y; Shows a Syntax Error because it is taken as
z=x++ ++y; by the Compiler.
4. z=x+++++y; Shows a Syntax Error because it is taken as
z=x++ ++ +y; by the Compiler.