Find String Length without using Predefined Function in C
The program calculates and prints the length of a given string.
	- It starts by declaring the variables i and c (a counter).
 
	- Then it takes a string input from the user using gets() and stores it in the str array.
 
	- The program prints the given string using puts(str).
 
	- A for loop is used to iterate over the string and count the number of characters in it. str[i]!='\0' checks if the current character is not the null terminator, indicating the end of the string.
 
	- The counter c is incremented for each character.
 
	- Finally, the length of the string is printed using printf("\nString Length:%d",c);
 
	- The program returns 0 to indicate successful execution.
 
Source Code
#include<stdio.h>
int main()
{
   int i,c=0;
   char str[100];
   printf("\nEnter the String:");
   gets(str);
   printf("\nGiven String:");
   puts(str);
   for(i=0;str[i]!='\0';i++)
   {
      c++;
   }
   printf("\nString Length:%d",c);
   return 0;
}
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Output
Enter the  String:Tutor Joe's
string length:11