C program to print a string

Printing strings

C program to print a string using various functions such as printf, puts. Consider the following code:

printf("Hi there! How are you doing?");

Output:
Hi there! How are you doing?

The printf function prints the argument passed to it (a string). Next, we will see how to print it if it's stored in a character array.

#include <stdio.h>
int main()
{
   char z[100] = "I am learning C programming language.";
   printf("%s", z); // %s is format specifier
   return 0;
}

Output:
I am learning C programming language.

To input a string, we can use scanf and gets functions.

C program

#include <stdio.h>
int main()
{
    char array[100];
    
    printf("Enter a string\n");
    scanf("%s", array);
    printf("Your string: %s\n", array);
    return 0;
}

Output:
Enter a string
We love C.
Your string: We

Only "We" is printed because function scanf can only be used to input strings without any spaces, to input strings containing spaces use gets function.

Input string containing spaces

#include <stdio.h>
int main()
{
  char z[100];
  printf("Enter a string\n");
  gets(z);
  printf("The string: %s\n", z);
  return 0;
}

Enter a string
Practice makes a person perfect.
The string: Practice makes a person perfect.

Print a string using a loop

We can print a string using a loop by printing its characters one at a time. It terminates with '\0' (NULL character), which marks its end.

#include <stdio.h>
int main()
{
   char s[100];
   int c = 0;
   gets(s);
   while (s[c] != '\0') {
      printf("%c", s[c]);
      c++;
   }
   return 0;
}

You can also use a for loop:

for (c = 0; s[c] != '\0'; c++) 
   printf("%c", s[c]);

Using a do-while loop:

#include <stdio.h>
int main()
{
   char s[100];
   int c = 0;
   gets(s);
   
   if (s[c] != '\0') { // Used to check empty string
     do {
       printf("%c", s[c]);
       c++;
     } while (s[c] != '\0');
   }
   return 0;
}