Breaking down into even more tokens?

This is a discussion on Breaking down into even more tokens? within the C Programming forums, part of the General Programming Boards category; Hello all, I am making a program that can solve for x. I have already made the program break the ...

  1. #1
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    Breaking down into even more tokens?

    Hello all,
    I am making a program that can solve for x. I have already made the program break the string into individual parts using strtok(). However, I don't know how to make the code that checks an individual token for x. For instance if I have 54x + 8 = 22. The program can break it into the tokens 54x, +, 8, = 22, but I don't know how to make the program recognize that 54 has an x in it. Any help would be appreciated.

    Thank you for reading this message

  2. #2
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    Look into the strchr() function in string.h, it will return a pointer to the first occurrence of the character or NULL if not found. It's also possible to create a similar function, that checks if each char in the string is equal to 'x'.

    Code:
            char *found = strchr(argv[1], 'x');
            if(found)
                    printf("%c\n", *found);
            else
                    printf("Not found");

  3. #3
    Registered User ssharish2005's Avatar
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    These sort things can be very easly be solved using the state machine. But here is an simple solution

    Code:
    char exp[] = "54x"; 
    char V;
    int d;
    
    if( sscanf( exp, "%d%c", &d, &V) == 2 )
        print d, V
    else
       print FAILED
    ssharish
    Life is like riding a bicycle. To keep your balance you must keep moving - Einstein

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