#include <iostream>
   #include <cstring>
 
   int main() {
       char a[] = "hello";
       std::cout << "a starts out as [" << a << "]\n";
 
       // C/C++ arrays are 0-based, that is:
       a[0] = 'H'; // changes a to "Hello"
 
       std::cout << "a is now [" << a << "]\n";
 
       std::cout << "strlen(a) returns " << strlen(a) << "\n";
 
       // But that is based on counting characters until the 0.
       a[3] = 0; // one way to write it,
       a[3] = '\0'; // some people prefer writing it this way.
 
       std::cout << "a changed to [" << a << "]\n";
 
       std::cout << "strlen(a) is now " << strlen(a) << "\n";
 
       return 0;
   }
 
 

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