How does this C++ while loop work?

Question

I learned the basics of C++ few months ago. Recently I found a while loop that looks like this. I want to understand how it works.

while(cin>>n>>m,n||m)
{
    does something;
}

Answer 1

operator , (operator comma) executes all instructions in list and returns value of last expression, so cin>>n>>m,n||m is equal to

cin >> n >> m;
n || m;

And whole loop will work like this one:

int n, m;
cin >> n >> m;
while(n || m){
    //some action
    cin >> n >> m;
}