Why is %c Used in C Programming

C is a general-purpose programming language widely used as a beginner language for coding. There are different data types for C, which include integer, float, and character. They need to be defined while creating any program. In C language, different format specifiers are used for printing output, including %d, %c, and others. So, if you want to know specifically about the %c format specifier and its usage in the C programming language, you can follow this guide.

Why is %c Used in C?

Just like any other programming language, C also has a fixed syntax that needs to be followed to create programs. The basic syntax of C is that users have to include the C header files first, which are <stdio.h> and <stdlib.h>. Then define a main function, which encloses all the main code of the program:

#include <stdio.h>
int main(void) {
}

And a print command is used to display the output. For instance, let’s try printing a letter k as an output and for that, use the below-written command inside the main function:

printf("%d", 'k');

In the output, you can see that instead of letter k, a number is displayed as an output. Confused?

Now let’s understand this concept of why a number is printed instead of the character k, so the answer is that a computer is a machine that works on numbers so each character or letter has an equivalent machine number (ASCII code) for it. For instance; in the above example the machine equivalent number for k is 107. If a user uses %d with a character then the program will display the ASCII code of the character and not the original character.

Like %d, the %c is used to display the original character. Now let’s run the same above command to print k just replace %d with %c, as shown below:

printf("%c", 'k');

Now in the output, you can clearly see that instead of a number, a letter k itself is printed. So, whenever users want to print a character, they can use %c inside the print command. The %c represents “character” and informs the compiler that a character output is required:

Using %c in Arrays

Now let’s print a character array using %c with a print command. In the below program, I have defined an array of 9 characters and I want to print these exact array elements one by one. For that, I have used a for loop inside which the printf command is present along with %c:

#include <stdio.h>
#include <stdlib.h>
int main(void) {

char array[] = {'L','I','N','U','X','H','I','N','T'};

for (int x = 0; x < 9; x++) {
printf("%c", array[x]);
printf("\n");
}
}

After running the program, you can see that the output has displayed the character one by one:

Now keep the program same and just replace %c with %d inside the printf command and notice the difference in the output:

#include <stdio.h>
#include <stdlib.h>
int main(void) {

char array[] = {'L','I','N','U','X','H','I','N','T'};

for (int x = 0; x < 9; x++) {
printf("%d", array[x]);
printf("\n");
}
}

Now in the output, you can see that by just changing the %c, the output has changed completely. Instead of characters, their ASCII codes are displayed:

Conclusion

The %c in C programming language is used to represent the character. Like if users want to print a character or an array of characters they can simply use %c with the printf command to inform the compiler that the output is required in the form of characters. If %d is used instead of %c, the output will change completely and instead of displaying the character output, it will display the ASCII code of each character.

Why is %c Used in C Programming

Why is %c Used in C?

Using %c in Arrays

Conclusion

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Zahra Zamir