C Program to Find Length of String with using user defined function

#include<stdio.h>
#include<conio.h>

int FindLength(char str[]);      // Prototype Declaration

void main()
{
 char str[100];
 int length;
 printf("\nEnter the String : ");
 gets(str);

 length = FindLength(str);

 printf("\nLength of the String is : %d",length);
 getch();
}

//Writing function

int FindLength(char str[])
{
 int len = 0;
 while(str[len]!='')
    len++;
 return(len);
}

Explanation of the program –

after accepting the string from the user we are passing the complete array to the function.

length = FindLength(str);

Now inside the function we are executing a while loop which will calculate the length of the string.

int FindLength(char str[])
{
 int len = 0;
 while(str[len]!='')
    len++;
 return(len);
}