Strings in C

In C programming language, a string is a sequence of characters that is terminated by a null character ‘\0’. Strings are commonly used to represent text in programs.

To declare a string in C, you can use an array of characters. Here’s an example of how to declare and initialize a string in C:

char str[] = "Hello, world!";

In this example, we declare a character array named “str” and initialize it with the string “Hello, world!”. The null character ‘\0’ is automatically added to the end of the string by the compiler.

We can also use pointers to manipulate strings in C. Here’s an example of how to use a pointer to access the characters of a string:

char str[] = "Hello, world!";
char *ptr = str;

while (*ptr != '\0') {
    printf("%c", *ptr);
    ptr++;
}
printf("\n");

In this example, we declare a character array named “str” and initialize it with the string “Hello, world!”. We then declare a pointer named “ptr” that points to the first character of the string. We use a while loop to iterate over the characters of the string using the dereference operator * to access the value stored at the memory address pointed to by the pointer. We print each character to the console until we reach the null character ‘\0’.

We can also use standard library functions to manipulate strings in C, such as strlen(), strcpy(), strcat(), and strcmp(). Here’s an example of how to use the strlen() function to find the length of a string:

#include 
#include 

int main() {
    char str[] = "Hello, world!";
    int len = strlen(str);

    printf("The length of the string is %d\n", len);

    return 0;
}

In this example, we include the string.h library to use the strlen() function. We declare a character array named “str” and initialize it with the string “Hello, world!”. We then use the strlen() function to find the length of the string and store it in the variable “len”. We print the length of the string to the console using printf().

Strings in C are a powerful feature that enable the programmer to work with text data efficiently. However, it is important to be careful when manipulating strings to avoid buffer overflows and other errors.