User input ending loops on C++
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I am trying to create something (I'm thinking probably a loop?) that will allow me to have the user enter several numbers and then enter something like "done" to get all the numbers added up.

for example if I have a float (call it x for now) they could enter "7 *enter* 5 *enter* 9 *enter* done *enter*" and it would add those numbers and make x that value. Where I am coming into problems is that I need the user to be able to be able to enter as many numbers as they want (between 1 and 70 as an example) without specifying how many numbers they want to enter, just entering something in when they are done.

Thank you all