How to exit a loop

[neoseeker191]

I am doing a homework assignment in which we have to get an undetermained amount of numbers from the user. I was wondering how to tell when the user is done entering numbers and wants to exit the loop, such as perhaps a blank space or a word like 'quit'.

Here is what I have so far, I used 72 as the exit number just as a test.

// Function Used to Get Numbers into Array
int  calcList() {

	for (int i=0; i<100; i++) {
		std::cout << "Enter an integer: ";
		 std::cin  >> list[i];
		 counter = counter + 1;
		 
		 // Exit Loop When 72 is Inputed
		 if (list[i]== 72) {
			 return(0);
		 }
		 
	}
}

Thank you.