When it comes to working with strings in the C programming language, one common task is to split a string into smaller parts based on a certain delimiter. The most commonly used delimiter is the space character, which is used to separate words in a sentence. In this article, we will explore different techniques for splitting a string by space in C.
Before we dive into the code, let's first understand the basic concept of strings in C. A string is simply a sequence of characters, terminated by the null character '\0'. So, when we say we want to split a string, what we actually mean is that we want to create multiple strings from a single string.
The most straightforward way to split a string by space is to use the C library function `strtok()`. This function takes two arguments - the string to be split and the delimiter. It returns a pointer to the first token (a substring) and modifies the original string by replacing the delimiter with a null character. Let's see an example:
```
#include <stdio.h>
#include <string.h>
int main(){
char str[] = "Splitting a String by Space in C";
char *token = strtok(str, " ");
while (token != NULL){
printf("%s\n", token);
token = strtok(NULL, " ");
}
return 0;
}
```
Output:
```
Splitting
a
String
by
Space
in
C
```
As you can see, the `strtok()` function splits the string at each space character and returns the words as tokens. The second argument of `strtok()` can be any character or a set of characters that you want to use as a delimiter.
But the problem with `strtok()` is that it modifies the original string, which may not always be desirable. To avoid this, we can use the `strndup()` function to create a copy of the original string and perform the splitting on the copy. Here's an example:
```
#include <stdio.h>
#include <string.h>
int main(){
char str[] = "Splitting a String by Space in C";
char *str_copy = strndup(str, strlen(str));
char *token = strtok(str_copy, " ");
while (token != NULL){
printf("%s\n", token);
token = strtok(NULL, " ");
}
free(str_copy);
return 0;
}
```
Output:
```
Splitting
a
String
by
Space
in
C
```
Another way to split a string by space is by using the `sscanf()` function. This function reads formatted input from a string and stores the results in the specified variables. We can use it to read words from a string, one by one, until we reach the end of the string. Here's an example:
```
#include <stdio.h>
#include <string.h>
int main(){
char str[] = "Splitting a String by Space in C";
