This C program prompts the user to enter a string and then calculates and displays the length of the string.
#include <stdio.h>
int main()
{
char some_string[100];
int x;
printf("Enter Some String: \n");
scanf("%s", some_string);
while (some_string[x] != '\0')
{
x++;
}
printf("Total Length: %d \n", x);
return 0;
}
Result:
Enter Some String:
something
Total Length: 9
Process returned 0 (0x0) execution time : 2.677 s
Press any key to continue.
Line by line explanation:
#include <stdio.h>
This line includes the standard input-output library header file, which is needed for using standard functions like printf() and scanf().
int main()
{
This is the starting point of the program where the main() function is defined. This function is required in every C program and serves as the entry point of the program. The function signature int main() indicates that the function returns an integer value upon completion.
char some_string[100];
int x;
This code block declares two variables: some_string, which is a character array of size 100 and x, which is an integer variable.
printf("Enter Some String: \n");
scanf("%s", some_string);
These lines of code print a prompt to the user to enter a string using printf() and then reads in the input string using scanf(). %s format specifier in the scanf() function indicates that it will read in a string of characters from the user.
while (some_string[x] != '\0')
{
x++;
}
This code block uses a while loop to iterate through the character array some_string until it reaches the null character '\0'. The null character marks the end of a C-style string. In each iteration, the loop increments the value of the x variable, which keeps track of the number of characters in the string.
printf("Total Length: %d \n", x);
return 0;
}
Finally, this code block uses printf() to display the length of the string by printing the value of the x variable. The program then returns 0 to indicate successful execution of the program.
