Thread: Looking at strings

  1. #1
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    Looking at strings

    (in C and only in C)
    hi, im reading from a file a number of items, eg....
    add(15);
    sum();
    add(100);
    sum();
    ok.......
    I am tokenizing the file then putting the tokens in an array. I then want to look at each token and then get the value from with the brackets of the add tokens

    eg add(50) value = 50.

    Cant think of a way to do this, can someone please help??? with a bit of code i could use?

    Thankyou very much in advance

  2. #2
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    Well, I won't do your homework for you but I'll give you an idea where you could start.

    I would start by making functions for the strings you read in... like a function for add(), sum(), etc

    And then in the main method, I would actually do the reading from the file and call the methods it asks for.

    Alexisa

  3. #3
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    ***THIS ISNT A HOMEWORK QUESTION*******

    Ok let me get rid of some of the extra detail and ask a simplier question,

    i have a string, there is(definatley) a number within the string, how can i find out the number???

    eg


    ifthenumberinthebracketsis50iwillbeveryhappy(50);

    This dos not mean that ifthenumberinthebracketsis50iwillbeveryhappy is a function but just a string.

  4. #4
    and the hat of int overfl Salem's Avatar
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    You could start with the strchr() function to locate the positions of the parentheses
    If you dance barefoot on the broken glass of undefined behaviour, you've got to expect the occasional cut.
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  5. #5
    ATH0 quzah's Avatar
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    Or perhaps a simple loop using isdigit to test each character for validity.

    Quzah.
    Hope is the first step on the road to disappointment.

  6. #6
    End Of Line Hammer's Avatar
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    Originally posted by quzah
    Or perhaps a simple loop using isdigit to test each character for validity.

    Quzah.
    Another option: you can use strcspn() to achieve a similar result.
    When all else fails, read the instructions.
    If you're posting code, use code tags: [code] /* insert code here */ [/code]

  7. #7
    Been here, done that.
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    Originally posted by quzah
    Or perhaps a simple loop using isdigit to test each character for validity.

    Quzah.
    That won't work based on his example. Find the open paren and test/read the number.
    Definition: Politics -- Latin, from
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  8. #8
    ATH0 quzah's Avatar
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    Originally posted by WaltP
    That won't work based on his example. Find the open paren and test/read the number.
    Sure it would.
    Code:
    for( x = 0; s[x]; x++ )
    {
        if( x > 0 && isdigit( s[x] ) && s[x-1] == '(' )
            printf("See? It works. You just have to be creative.\n");
    }
    Quzah.
    Hope is the first step on the road to disappointment.

  9. #9
    Been here, done that.
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    Originally posted by quzah
    Sure it would.
    Code:
    for( x = 0; s[x]; x++ )
    {
        if( x > 0 && isdigit( s[x] ) && s[x-1] == '(' )
            printf("See? It works. You just have to be creative.\n");
    }
    Quzah.
    OK, smartypants, try it on
    ThisIsA30CharacterFunctionName(15) without the paren check, as you implied before!
    Definition: Politics -- Latin, from
    poly meaning many and
    tics meaning blood sucking parasites
    -- Tom Smothers

  10. #10
    ATH0 quzah's Avatar
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    Originally posted by WaltP
    OK, smartypants, try it on
    ThisIsA30CharacterFunctionName(15) without the paren check, as you implied before!
    I didn't say anything about a paren check. I said a simple loop using isdigit. My last example fits that description.


    Quzah.
    Hope is the first step on the road to disappointment.

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