c++ - Pointer to an array,why is this the address of the last element? -


i working tutorials point.com example.

int  var[max] = {10, 100, 200}; int  *ptr;  // let have address of last element in pointer. ptr = &var[max-1]; (int = max; > 0; i--) {     cout << "address of var[" << << "] = ";     cout << ptr << endl;      cout << "value of var[" << << "] = ";     cout << *ptr << endl;      // point previous location     ptr--; } return 0;

so, why &var[max - 1] , why not &var[max]? if not use reference, possible solve problem in different manner?

because arrays in c++ zero-based, i.e. start 0 , end @ n-1. var[max] element past end of array, out-of-bounds , accessing undefined behaviour.

var   { 10, 100, 200 } index   ^0  ^1^  ^2^   ^3?

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