Myujth

I have try and figure why am I getting error messages to create bubble sort from file. It can be any from file depending on when I do labcheck command. This is over due but I really want to know why. The comments in the C programming are the directions by CS instructor. Any one can help how to fix the C program?

This is when I labcheck:

p8.c: In function ‘main’:
p8.c:63:24: warning: format ‘%s’ expects a matching ‘char *’ argument [-Wformat=]
 printf ("Usage: %s <file>n");/*this should be followed as from
 ~^
p8.c:67:22: warning: implicit declaration of function ‘atof’; did you mean ‘feof’? [-Wimplicit-function-declaration]
 char array = atof (argv[2]);
 ^~~~
 feof
p8.c:67:22: error: invalid initializer
p8.c:68:18: warning: passing argument 1 of ‘bubblesort’ from incompatible pointer type [-Wincompatible-pointer-types]
 bubblesort(array, 100);
 ^~~~~
p8.c:25:24: note: expected ‘char **’ but argument is of type ‘char *’
 void bubblesort (char *A, int n)
 ~~~~~~^~~
make: *** [Makefile:37: p8.o] Error 1
-4.0 p8 failed to compile.

This is my code assignment:

/* 4 points */
#include <stdio.h>
#include <string.h>

#define MAXLEN 1000

/**
 * Fill in the bubblesort function: https://en.wikipedia.org/wiki/Bubble_sort
 * Using this pseudo-code, convert to C code:
 * procedure bubbleSort( A : list of sortable items, n : length(A) )
 * repeat
 * newn = 0
 * for i = 1 to n-1 inclusive do
 * if A[i-1] > A[i] then
 * 

 swap(A[i-1], A[i])
 * newn = i
 * end if
 * end for
 * n = newn
 * until n <= 1
 * end procedure
 */
void bubblesort (char *A, int n)

 int i, j, temp;
 int length;

 for (i = 0; i < length; i++)
 
 for (j = 0; j < length - 1; j++)
 
 if (*A[j + 1] < *A[j])
 
 temp = *A[j];
 *A[j] = *A[j + 1];
 *A[j + 1] = temp;
 
 
 

/**
 * Create a main function that opens a file composed of words, one per line
 * and sorts them using the bubble-sort algorithm.
 * Usage: "Usage: %s <file>n"
 * Example input/output:
 * ./p8 testfile
 * Bob
 * Bubbles
 * Butters
 * Dave
 * ...
 */

int main (int argc, char *argv) 
 int rc, i;//rc is Read Character 

 if (argc < 2)
 
 printf ("Usage: %s <file>n");/*this should be followed as from 
 instruction, nothing can be change due to error message.*/
 rc = -1;
 else 
 char array = atof (argv[2]);
 bubblesort(array, 100);
 rc = 0;
 while (rc < i)
 
 printf ("%cn", array[rc]);
 rc++;
 
 
 // prints print new lines from file 
 return 0;

There are a number of bugs. I created two versions of your code. One with the bugs annotated. And another cleaned up and working version.

Here's the annotated version:

/* 4 points */
#include <stdio.h>
#include <string.h>

// NOTE/BUG: we need this for atof
#if 1
#include <stdlib.h>
#include <errno.h>
#endif

#define MAXLEN 1000

/**
 * Fill in the bubblesort function: https://en.wikipedia.org/wiki/Bubble_sort
 * Using this pseudo-code, convert to C code:
 * procedure bubbleSort( A : list of sortable items, n : length(A) )
 * repeat
 * newn = 0
 * for i = 1 to n-1 inclusive do
 * if A[i-1] > A[i] then
 *

 swap(A[i-1], A[i])
 * newn = i
 * end if
 * end for
 * n = newn
 * until n <= 1
 * end procedure
 */
void
bubblesort(char *A, int n)

 int i,
 j,
 temp;
 int length;

// NOTE/BUG: temp needs to be "char *temp"
// NOTE/BUG: "length" should be "n" here
// NOTE/BUG: replace all "*A[whatever]" with "A[whatever]"
 for (i = 0; i < length; i++) 
 for (j = 0; j < length - 1; j++) 
// NOTE/BUG: we need strcmp here
 if (*A[j + 1] < *A[j]) 
 temp = *A[j];
 *A[j] = *A[j + 1];
 *A[j + 1] = temp;
 
 
 


/**
 * Create a main function that opens a file composed of words, one per line
 * and sorts them using the bubble-sort algorithm.
 * Usage: "Usage: %s <file>n"
 * Example input/output:
 * ./p8 testfile
 * Bob
 * Bubbles
 * Butters
 * Dave
 * ...
 */

int
main(int argc, char *argv)

 int rc,
 i; // rc is Read Character

 if (argc < 2) 
/* this should be followed as from instruction, nothing can be change due to
error message. */
// NOTE/BUG: this is missing the argv[0] argument
#if 0
 printf("Usage: %s <file>n");
#else
 printf("Usage: %s <file>n",argv[0]);
#endif
 rc = -1;
 
 else 
// NOTE/BUG: this is too short (i.e. it needs to be 100)
// NOTE/BUG: we need to read in the values
#if 0
 char array = atof(argv[2]);
 bubblesort(array, 100);
#else
 char *array[100];

// NOTE/BUG: this should be argv[1]
 FILE *fi = fopen(argv[2],"r");
 if (fi == NULL) 
 printf("unable to open '%s' -- %sn",argv[2],strerror(errno));
 exit(1);
 

 int arrcnt = 0;
 while (1) 
 char buf[1000];
 char *cp = fgets(buf,sizeof(buf),fi);
 if (cp == NULL)
 break;

 cp = strchr(buf,'n');
 if (cp != NULL)
 *cp = 0;

 cp = strdup(cp);
 array[arrcnt++] = cp;
 

 fclose(fi);

 bubblesort(array,arrcnt);
#endif

 rc = 0;
 while (rc < i) 
// NOTE/BUG: this should be "%s"
 printf("%cn", array[rc]);
 rc++;
 
 

 // prints print new lines from file
 return 0;

Here's the cleaned up and working version:

/* 4 points */
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <errno.h>

#define MAXLEN 1000

/**
 * Fill in the bubblesort function: https://en.wikipedia.org/wiki/Bubble_sort
 * Using this pseudo-code, convert to C code:
 * procedure bubbleSort( A : list of sortable items, n : length(A) )
 * repeat
 * newn = 0
 * for i = 1 to n-1 inclusive do
 * if A[i-1] > A[i] then
 *

 swap(A[i-1], A[i])
 * newn = i
 * end if
 * end for
 * n = newn
 * until n <= 1
 * end procedure
 */
void
bubblesort(char *A, int n)

 int i, j;
 char *temp;

 for (i = 0; i < n; i++) 
 for (j = 0; j < n - 1; j++) 
 if (strcmp(A[j + 1],A[j]) < 0) 
 temp = A[j];
 A[j] = A[j + 1];
 A[j + 1] = temp;
 
 
 


/**
 * Create a main function that opens a file composed of words, one per line
 * and sorts them using the bubble-sort algorithm.
 * Usage: "Usage: %s <file>n"
 * Example input/output:
 * ./p8 testfile
 * Bob
 * Bubbles
 * Butters
 * Dave
 * ...
 */

int
main(int argc, char *argv)

 int rc = 0;

 if (argc < 2) 
 /* this should be followed as from instruction, nothing can be change
 due to error message. */
 printf("Usage: %s <file>n",argv[0]);
 rc = 1;
 
 else 
 char *array[100];
 int arrmax = sizeof(array) / sizeof(array[0]);

 FILE *fi = fopen(argv[1],"r");
 if (fi == NULL) 
 printf("unable to open '%s' -- %sn",argv[1],strerror(errno));
 exit(1);
 

 int arrcnt = 0;
 while (1) 
 char buf[MAXLEN];
 char *cp;

 cp = fgets(buf,sizeof(buf),fi);
 if (cp == NULL)
 break;

 if (arrcnt >= arrmax) 
 printf("too many input linesn");
 exit(1);
 

 cp = strchr(buf,'n');
 if (cp != NULL)
 *cp = 0;

 cp = strdup(buf);
 array[arrcnt++] = cp;
 

 fclose(fi);

 bubblesort(array,arrcnt);

 for (int arridx = 0; arridx < arrcnt; ++arridx)
 printf("%sn", array[arridx]);
 

 // prints print new lines from file
 return rc;