Printing back arrays

This is a discussion on Printing back arrays within the C Programming forums, part of the General Programming Boards category; I'm trying to print back an arrays of char's but all I'm getting is garbage? Anyone know a better way ...

  1. #1
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    Printing back arrays

    I'm trying to print back an arrays of char's but all I'm getting is garbage? Anyone know a better way to do this?

    #include <stdio.h>

    int main ( ) {

    int SIZE = 80;

    char string[SIZE];

    printf("Input a sentance: ");
    scanf("%s", &string);

    for(int i=1;80>=i;i++){
    putchar(string[--SIZE]);
    }

    return 0;
    }

  2. #2
    and the hat of wrongness Salem's Avatar
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    The array is initialised with garbage characters, and scanf will not necessary write to the whole array.

    You should call strlen to determine the number of valid characters in the array.
    If you dance barefoot on the broken glass of undefined behaviour, you've got to expect the occasional cut.
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  3. #3
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    Thanks you.

  4. #4
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    Hi this should fix it............
    Code:
    #include <stdio.h>
    #include <string.h>
    #define SIZE  80  
    
    int main ( ) { 
    
    char string[SIZE];
    int len; 
    
    printf("Input a sentance: "); 
    /*scanf will read to first space character so use*/
    gets(string);
    /*  loop initialized to string length minus null char*/
    /*  then decrement until = to first element = 0  */ 
    len = strlen(string) - 1;
    for(i = len; i >= 0; i--)    /* post decrement*/
           putchar(string[i]);     /* not SIZE but i  */
    }
    hoping to be certified (programming in c)
    here's the news - I'm officially certified.

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