Thread: Need Help with this!

I am trying to make a program that will later one test myself by asking me standard idoms(this is not a assignment this is me practicing for my midterm).

I am trying to make a check to compare my user input answer compared to the correct standard idom

I am currently working on a standard idom to "procces an array"

size_t i;
for(i = 0; i < n; i++)

I am currently working on a regular expresion on the for loop part this is what I have.


if(sscanf(line2, "%[^([a-z][]=[][0-9];[][a-z][]<[][a-z];[][a-z++])",holdLoop)==1)

but this does not seem to work. Also if anyone has a site with C sscanf regular expresion that would be very helpful(since I got alot of standard idoms to write with different expresions.

Here is my whole code.

[code]

Code:

#include <stdio.h>
#include <string.h>


void idiom1(char idiomOne[]);
int main()
{
	char prompt[] = "Please Enter In the correct idiom";
	char idomOne[] = "Standard idom to process an array";
	
	idiom1(idomOne);
	return 0;
}

void idiom1(char idiomOne[])
{
	char varType[1024];
	char line[1024];
	char compare[] = "size_t i;";
	char forLoop[] = "for(i = 0; i < n; i++)";
	char holdLoop[1024];
	char line2[1024];
	char prompt[] = "Enter the loop part now: ";
	int  i;
	
	while(1)
	{
		
		printf("%s: ", idiomOne);
	
		if(fgets(line, 1024, stdin) == 0)
		{
			clearerr(stdin);
			break;
		}
		
		for (i = 0; line[i] != '\0'; i++)
		{
			if (line[i] == '\n')
			{
				line[i] = '\0';
			}
		}
		
		if(sscanf(line, "%[^[][a-z];", varType) == 1)
		{	
			if(!strcmp(varType, compare))
			{
				printf("This is correct:");
				printf("%s",prompt);
				if(fgets(line2,1024,stdin) == 0)
				{
					clearerr(stdin);
					break;
				}
				if(sscanf(line2, "%[^([a-z][]=[][0-9];[][a-z][]<[][a-z];[][a-z++])",holdLoop)==1)
				{
					fprintf(stderr,"does this work");
					if(!strcmp(holdLoop,forLoop))
					{
						printf("correct for line2");	
					}
					else
					{
						printf("NOT correct for line2");
					}
					
				}
			}
			else
			{
				printf("NOT What VarType Held %s \n", varType);
			}
		}
	}
		
	
}

scanf() doesn't support regular expressions. To learn about scanf() and its format string look here: http://www.die.net/doc/linux/man/man3/sscanf.3.html

Just because it compiles doesn't mean it works. So "completely allowed" doesn't mean jack in this case.


Quzah.

Originally Posted by chobo2

I just don't know how many and what they look like.

I posted a link that explains exactly how many there and exactly what they look like. How spoonfed do you need to be? Why ask for help if you're not going to listen?

> Ok I guess there not called regular expresion
No, they're called scan-sets
So [a-z][a-z] is still just [a-z]
They're a very pale imitation of true regular expressions.

> "%[^([a-z][]=[][0-9];[][a-z][]<[][a-z];[][a-z++])"
Which means what exactly?
None of the following bunches of characters?

> for(i = 0; i < n; i++)
Are you going to interpret this in some way (like a compiler would)?
At the moment, it just seems like you're just using strcmp() to match the whole input with the predefined answer.

You may as well just use fgets(), strip off the newline and then compare with your prepared answer.

But if the prepared answer is
"size_t i;";
"for(i = 0; i < n; i++)";
And you want to allow
"int j;"
"for ( j = 0 ; j < x ; j++ )"
as being an equivalent answer based on patterns in the code, then you need another approach.

> but what I did is completly allowed I believe it just does not work
So long as the " " match at both ends of the string, the compiler won't give a monkey's what you pass to sscanf.
And sscanf() has no means of returning "your scanset is bogus", it will just return with 0 or EOF.

Pet peeve, use a thread title that relates to your question... "Need help with this!" that would probably be self evident with the contents of the thread. "Regex help" or "sscanf() help" would be more appropriate.