A C++ Mistake

Consider this piece of code:

int f = 10;

int ff() {
    return f = 5;
}

int main() {
    printf("%d %d\n", ff(), f);
    return 0;
}

As I have expected it to print "5 5" (I was using Dev C++) so did I get, but I didn't know it was wrong until the judge showed me the famous and fabulous "WA". The correct output is "5 10", because, function parameters are though of to be similar as assignment operation and should be performed from right to left. Now it makes sense. But got some penalty for stupid yet adorable Dev C++. However, I've learnt this... that's the good side of it! So, you too be careful if you don't know that already.