Count the number of arrays with pointers

Using the array address subtraction to calculate the number of elements of the array

Log in and copy

      
      

       
       #define _CRT_SECURE_NO_WARNINGS 1
       
       

       
       #include<stdio.h>
       
       

       
       

       
       int 
       
       my_strlen(
       
       char
       
       * 
       
       str)
       
       
{
       
       
  
       
       char
       
       * 
       
       star 
       
       = 
       
       str;
       
       
  
       
       char
       
       * 
       
       end 
       
       = 
       
       str;
       
       
  
       
       while (
       
       *
       
       end 
       
       != 
       
       '\0')
       
       
  {
       
       
    
       
       end
       
       ++;
       
       
  }
       
       
  
       
       return 
       
       end 
       
       - 
       
       star;
       
       

       
       
}
       
       

       
       int 
       
       main()
       
       
{
       
       
  
       
       char 
       
       arr[] 
       
       = 
       
       "bit";
       
       
  
       
       int 
       
       len 
       
       = 
       
       my_strlen(
       
       arr);
       
       
  
       
       printf(
       
       "%d\n", 
       
       len);
       
       

       
       
  
       
       

       
       
  
       
       return 
       
       0;
       
       
}
      
      
      
      

       
       
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