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stack for Matching <<.. char array??

code101 (4)
hello i am writing a program for matching << and >> pointers using a stack but somehow need this char < to be distinguished from < (the same character) so they can match on the stack....thinking I should put it in some sort of array but not sure how to do that any help appreciated...
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//parenthases
	char L_paren = '(';
	char R_paren = ')';
	//braces
	char L_brace = '{';
	char R_brace = '}';
	//Square brackets
	char L_square = '[';
	char R_square = ']';
	//pointers
	  char c_out_left = '<';
	  char c_out_right = '<';
	//pointers
	char c_in_right = '>';
	char c_in_left = '<';

	bool error = false; 
	char sym;

	in.get(sym);

	while (( sym != '\n')  && (!error) )
	{
		if (sym == L_paren || sym==L_brace || sym==L_square|| sym==c_out_left ||sym==c_in_left)

			push(s,sym);//intialize function push

		if (sym == R_paren || sym==R_brace || sym==R_square || sym==c_out_right|| sym==c_in_right)

			if (isEmpty(s))
			{

				cout<<"\nUnmatched closing bracket '" << sym <<"' detected." <<endl;
				error = true;
			}
			else

				pop(s,sym);
		        in.get(sym);
	}

Last edited on
jsmith (5804)
I was waiting for that question.

If you are going to process the string at a character level, you need a state machine.

In State 0, if you see a '<', go to state 1.
In State 0, if you see a '>', go to state 2.
In State 1, if you see another '<', you've matched '<<', push and goto state 0.
In State 2, if you see another '>', you've matched '>>', pop and goto state 0.

I'll let you think about the error cases.
code101 (4)
THink i got it now thanks for helping
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