Finding a repeating number in an array?

This is a discussion on Finding a repeating number in an array? within the C Programming forums, part of the General Programming Boards category; Is there a way to find if a number is in an array more than once? How would I go ...

  1. #1
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    Finding a repeating number in an array?

    Is there a way to find if a number is in an array more than once? How would I go about doing this? Thanks for the help.

  2. #2
    Mad OnionKnight's Avatar
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    Iterate through the whole array and have a variable that increments for each time it finds that an element equals a certain number.

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    Okay, I figured that out. Thanks for the help. I have a new problem though, which should be easy for anyone who isn't me to figure out. I have the user enter his first and last name and favorite number, and then have the program print it out. However, It will not say "Hello, First name Last name!" but rather it will display the first name, then the second name on a new line.

    Code:
        printf( "Please enter your first name:\t " );
        fgets(str, 20, stdin);
        printf("\nPlease enter your last name:\t");
        fgets(lastname, 20, stdin);
        printf("\nWhat is your favorite number?\t");
        scanf("%d", &number);
        
        printf("Hello, %s %s!  I see that your favorite number is %d!\n", str, lastname, number);

    Also, I need to use fgets because I am using pointers for another part.

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    If it fits, fgets will also read the \n into the buffer, that's why the last name is being printed on the other line. There are many ways to get rid of the \n. I personally do it like this:
    Code:
    #include <string.h>
    char *p;
    
    if ((p = strchr(str, '\n')))
        *p = '\0';

  5. #5
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    Ah! Thanks a lot!

  6. #6
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    Quote Originally Posted by tcpl
    If it fits, fgets will also read the \n into the buffer, that's why the last name is being printed on the other line. There are many ways to get rid of the \n. I personally do it like this:
    Code:
    #include <string.h>
    char *p;
    
    if ((p = strchr(str, '\n')))
        *p = '\0';
    As well as getting into the habbit of checking that the pointer doesn't equal NULL before trying to utilize it.
    Granted from getting input from the user there should be a new line character but getting into the habbit is good because if you're reading from a user supplied file killing new line characters in that method without checking first can bite you.

  7. #7
    Frequently Quite Prolix dwks's Avatar
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    That's what the if statement does, makes sure p isn't NULL.
    dwk

    Seek and ye shall find. quaere et invenies.

    "Simplicity does not precede complexity, but follows it." -- Alan Perlis
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  8. #8
    Sys.os_type="Unix";;
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    Quote Originally Posted by dwks
    That's what the if statement does, makes sure p isn't NULL.
    Oops should of looked at the code closer before posting -.- sorry

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