sscanf (I think)

Im having some difficulties inputing elements into an array using sscanf. (The book Im using only has one like about sscanf). Anyway, all Im trying to do is input numbers into an array using fgets and sscanf, then print them.

I dont think Im too far off but I dont know what else to try.

Code:

---

static int valid( char array[], int count )
{ 
        int i = 0, decCount = 0, negCount = 0;

        for( i = 0; i < count; i++)
  {
                if( array[i] == '\n' ) continue;

                if(( array[i] < '0' || array[i] > '9' ) && array[i] != '.' && array[i] != '-')
                return BOOL_TRUE;
               
                if( array[i] == '.' )
                        decCount++;
                else if( array[i] == '-' )
                        negCount++;

                if( decCount > 1 || negCount > 1 )
                        return BOOL_FALSE;
        }
        return BOOL_TRUE;
}


int main (void)
{
        int maxnum;
        int e;
        char a[BUFSIZ];

        printf("How many numbers would you like to sort?\n");
        scanf("%d%*c", &maxnum);
        printf("\nPlease begin entering your %d numbers.\n", maxnum);
 
// GATHER DATA
        for( e = 0; e < maxnum; e++)
        {
                printf( "Enter number %d : ", e + 1 );
                fgets( a, BUFSIZ, stdin );

                while( valid( a, strlen(a) ) == BOOL_FALSE )
                {
                        printf( "Invalid Integer.\n" );
                        printf( "Please re-enter number %d: ", e + 1 );
                        fgets( a, BUFSIZ, stdin );
                }

#if 0
                sscanf( a, "%d", a[e] );
#endif
       
        }

// OUTPUT
        printf("\n\n  Output");
        printf("\n ================ ");

        for (e = 0; e < maxnum; e++)
        {
                printf("\n  %c", a[e] );
        }

        return 0;
}

---

Since you are accessing a single cell in the array, you must use its address:

sscanf( line, "%c", &array[x] );

Because you're reading into a single cell (ie: a single character).

Quzah.

pardon my ignorance, but isnt that what I was doing with sscanf( a, "%c", &a[e] ); ?

You are using a as your buffer for input, that means that it probably will not work as you want with sscanf. Declare another array to hold the final results:

Code:

---

#include <stdio.h>

int main ( void )
{
  /* Only used for input */
  char buffer[BUFSIZ];
  /* Only used for processed data */
  int final[2];
  int ret;

  printf ( "Enter two integers: " );
  if ( fgets ( buffer, sizeof buffer, stdin ) != NULL ) {
    /* scan from buffer to final */
    ret = sscanf ( buffer, "%d %d", &final[0], &final[1] );
    if ( ret != 2 )
      perror ( "An error was detected" );
    else
      printf ( "%d\n%d\n", final[0], final[1] );
  }
  return 0;
}

---

-Prelude

Quote:

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Originally posted by RyeDunn
pardon my ignorance, but isnt that what I was doing with sscanf( a, "%c", &a[e] ); ?

---

Nope. Look at your code. You are not using the & symbol. (CTRL+F, type in sscanf, and watch the occurances in the page)

You have, and I quote:

Quote:

---

Code:

---

#if 0
                sscanf( a, "%d", a[e] );
#endif

---

---

No & symbol.

Quzah.

I knew if I put that it would have been something that was pointed out....

I did try that and I do have that now but Im still having problems... Im at home now (and drunk if you dont mind, hah) so I cant specifically tell you whats wrong but I definately will 10 hrs from now!....

Thnx Quz
Rye

P.S. WHOO HOO! 30 Posts... Im no longer a jr memeber! (which basically means I have earned the title of "this guy wont give up")

If you look at the progs output, it appears that the following number entered always writes over the previous number and splits the numbers into individual characters and puts each into its own cell, see bleow.

Code:

---

Please begin entering your 5 numbers
Enter number 1 : 632
Enter number 2 : 5
Enter number 3 : 6
Enter number 4 : 2
Enter number 5 : 85


  Before Sorting
 ================
 0
  8  <-- first digit of last number
 1
  5  <-- last digit of last number
 2


 3

 4
    Press any key to continue

---

Now if you look at the code I am writing the line by using: sscanf(a, "%s", &a[e] ); Where a = array and e = cell or element number.

Code:

---

int main (void)
{
        int maxnum;
        int e;
        char a[BUFSIZ];

        printf("How many numbers would you like to sort?\n");
        scanf("%d%*c", &maxnum);
        printf("\nPlease begin entering your %d numbers.\n", maxnum);
 
// GATHER DATA
        for( e = 0; e < maxnum; e++)
        {
                printf( "Enter number %d : ", e + 1);
                fgets( a, BUFSIZ, stdin );

                while( valid( a, strlen(a) ) == BOOL_FALSE )
                {
                        printf( "Invalid Integer.\n" );
                        printf( "Please re-enter number %d: ", e + 1 );
                        fgets( a, BUFSIZ, stdin );
                }

#if 0
                sscanf(a, "%s", &a[e] );
#endif
       
        }

// BEFORE SORT
        printf("\n\n  Before Sorting");
        printf("\n ================ ");

        for (e = 0; e < maxnum; e++)
        {
                printf("\n %d ", e);  //For debuging purposes
                printf("\n  %c ", a[e] );
        }

        return 0;
}

---

Could one of you C Gurus please look at this and let me know what Im doing wrong? Much Thanks!

You haven't been listening to me, you are trying to read from a into a with sscanf. This is very likely not what you want, try this and see what I do differently:

Code:

---

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

#define DEBUG

#define BOOL_TRUE  1
#define BOOL_FALSE 0

static int valid( char array[], int count )
{ 
  int i = 0, decCount = 0, negCount = 0;
 
  for( i = 0; i < count; i++)
  {
    if( array[i] == '\n' ) continue;
   
    if(( array[i] < '0' || array[i] > '9' ) && array[i] != '.' && array[i] != '-')
      return BOOL_FALSE;
   
    if( array[i] == '.' )
      decCount++;
    else if( array[i] == '-' )
      negCount++;
   
    if( decCount > 1 || negCount > 1 )
      return BOOL_FALSE;
  }
  return BOOL_TRUE;
}

int main (void)
{
  int maxnum;
  int e;
  /* Use this for input */
  char a[BUFSIZ];
  /* Take from a and place the values here */
  double final[BUFSIZ] = {0.0};

  printf("How many numbers would you like to sort?\n");
  scanf("%d%*c", &maxnum);
  /* Check that scanf worked */
  printf("\nPlease begin entering your %d numbers.\n", maxnum);

  for( e = 0; e < maxnum; e++)
  {
    printf( "Enter number %d : ", e + 1);
    fgets( a, BUFSIZ, stdin );
    /* Check that fgets worked */

    while( valid( a, strlen(a) ) == BOOL_FALSE )
    {
      printf( "Invalid Integer.\n" );
      printf( "Please re-enter number %d: ", e + 1 );
      fgets( a, BUFSIZ, stdin );
      /* Check that fgets worked */
    }
    sscanf(a, "%lf", &final[e] );
    /* Check that sscanf worked */
  }

  printf("\n\n  Before Sorting");
  printf("\n ================\n");
 
  for (e = 0; e < maxnum; e++)
  {
#ifdef DEBUG
    printf("%d: ", e);
#endif
    printf("%f\n", final[e] );
  }
  return 0;
}

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-Prelude