Thread: how to break a string into array of strings

KBrigg's post above tells you how to do that. Keep in mind, however, what Sebastiani pointed out - be careful of multiple consecutive spaces, and spaces at the beginning / end of your string (but you should try and get it working on a simple string first - then get it to handle multiple spaces, etc...)

i tried to use sscanf too

Code:

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

typedef struct node node;
struct node{
	int value;
	struct node * next;
};
 int countletters(char *str);
 char * sortbycount(char* str);
void main()
{
	int g;
	char  str[18]="aabx bXcb bBxaDAa";
	char * r;
	g=countletters(str);
	r=sortbycount(str);
}


int countletters(char *str)
{
	int i,cnt=0;
	int ch[26]={0};
    for (i=0;i<(int)strlen(str);i++)
	{
       if ((str[i]>='a')&&(str[i]<='z'))
	   {
          ch[str[i]-'a']=1;
	   }
	   if ((str[i]>='A')&&(str[i]<='Z'))
	   {
          ch[str[i]-'A']=1;
	   }
	}
	for (i=0;i<26;i++)
	{
		if(ch[i]==1){ cnt++;}
	}
	printf("%d",cnt);
   return cnt;
}

char * sortbycount(char* str)
{
  int start=0,t=0,i,cnt=0;char** arr;
  for (i=0;i<(int)strlen(str);i++)
  {
    if (str[i]==' ') cnt++;
  }
  arr=(char**)malloc(sizeof(char*)*(cnt+1));
  i=0;
  do
  {
     for (i=start;str[i]!=' ';i++);
     arr[t]=(char*)malloc(sizeof(char)*(i-start+1));
     sscanf(arr[t],"%s",str+start); 
	 printf("%s",arr[t]);
	 start=i;
   t++;
  }while(t<cnt);
  
 return str;
}

when i do scanf("%s",str);
it should stop copying from stdin on enter or space

correct ?

No - %s copies a string. A string is a null-terminated array of chars. A space is a character. You should know that by looking at the documentation. You should also know that by having done a small test. Why didn't you write a small program to test that?

i know that there is some command for which %d %s
stops when there is a space

I am really curious, so I decided to write this nonrelevant contribution to the topic at hand: don't you guys have better things to do than waste your time and energy on this guy?

i know that there is some command for which %d %s
stops when there is a space

How do you know that? I'm looking through every reference I can find and I see no such thing. I've also never heard of it before. I'm not saying it doesn't exist, because I could be wrong, but I'm pretty sure you're gonna have to go along the lines of what KBriggs suggested.

don't you guys have better things to do than waste your time and energy on this guy?

He should be glad that the project I'm debugging has huge build-times. Though transgalactic2, I'm getting really close to closing this thread- there really isn't anything else anyone can do that will really help you.

there is that thing in fscanf
[^$] (copy till you get char $)

but i learned that we dont write in fscanf
%[^ ]

but we just write %s or %d
and it stops on space

i did that on files

and it should work too on sscanf

(append every char is not practical solution in a test ,i dont have so much time)

the great thing about writing code is that is takes basically the same amount of human time to do it character by character or by string, since loops are so helpful

And since string operations in c are such a pain in the ass to get right, you are more likely to get character by character code right if you are writing it on a test anyway. Plus you don't have to deal with all that crap about spaces etc.

isn't there an example in K&R that deals with this kind of thing?

You must be referring to this, though I didn't know this existed:

Matches a nonempty sequence of characters from the specified set of accepted characters; the next pointer must be a pointer to char, and there must be enough room for all the characters in the string, plus a terminating null byte. The usual skip of leading white space is suppressed. The string is to be made up of characters in (or not in) a particular set; the set is defined by the characters between the open bracket [ character and a close bracket ] character. The set excludes those characters if the first character after the open bracket is a circumflex (^). To include a close bracket in the set, make it the first character after the open bracket or the circumflex; any other position will end the set. The hyphen character - is also special; when placed between two other characters, it adds all intervening characters to the set. To include a hyphen, make it the last character before the final close bracket. For instance, [^]0-9-] means the set "everything except close bracket, zero through nine, and hyphen". The string ends with the appearance of a character not in the (or, with a circumflex, in) set or when the field width runs out.

According to this,

Code:

[^ ]

would exclude everything but the spaces. But I'm not sure that it stops reading when it encounters a space. It almost sounds like it just excludes those characters. Here's an exercise: try it and see which one is true.

may be this is what you're looking for. but this is not correct way of doing you can reduce lot of code using sscanf as pointed earlier, but just in case

Code:

#include <stdio.h>

int main()
{
 char strInput[80],strFinalWords[10][20];

 int intIndex,intLength,intTempCounter = 0,intWordCounter = 0;

 printf("Enter Any String :");
 gets(strInput);
 for(intIndex = 0 ; strInput[intIndex] != '\0' ; intIndex++)
 {
	if(strInput[intIndex] == ' ')
	{
		strFinalWords[intWordCounter][intTempCounter] = '\0';
		if(intIndex > 0 && strInput[intIndex - 1] != ' ')
		{
			intTempCounter = 0;
			intWordCounter++;
		}
		continue;
	}
	strFinalWords[intWordCounter][intTempCounter] = strInput[intIndex];
	intTempCounter++;
 }
 strFinalWords[intWordCounter][intTempCounter] = '\0';

 for(intIndex = 0 ; intIndex <= intWordCounter ; intIndex++)
	printf("%s\n",strFinalWords[intIndex]);

 return 0;
}

From the "it compiles so its fine by me" category :

Code:

char **split_str(char *str)
{
   int words = strlen(str) + 1;
   char **arr = calloc(words, sizeof(*arr));

   for (; isspace(*str); str++);
        words = 0;

   while (*str)
   {
      arr[!isspace(32)] = str;
      for (arr += 1; *str && !isspace(*str); str++);
         if (*str && !(*str = '\0')) str++;
      for (words += 1; *str && isspace(*str); str++);
   }

   return arr - words;
}

Unlike the other solutions posted, this doesn't waste space making extra copies of the string. Whether or not that's a good thing is open to debate, though

Hopefully no one turns this in as homework (or if they do, I hope they get what they deserve) so I think this is within the rules of the forum.