C program to find string length

1) Find length of string in c language using pointer

 #include <stdio.h>  
 int main()  
 {  
   char arr[100], *p;  
   int length = 0;  
   printf("Enter String : ");  
   gets(arr);  
   p = arr;  
   while( *( p + length ) )  
     length++;  
   printf("String Length = %d", length);  
   return 0;  
 }  

2) Find length of string in c language without using pointer

 #include <stdio.h>  
 int main()  
 {  
   char str[100];  
   int i, length = 0;  
   printf("Enter String : ");  
   gets(str);  
   for (i = 0; str[i] != '\0'; i++)  
   {  
     length++;  
   }  
   printf("String Length = %d", length);  
   return 0;  
 }