In the following snippet of code I have noticed ampersand is used even though we aren't manipulating the string. Can anyone please tell me why it's needed?
bool compare(string &s1,string &s2)
{
return s1.size() < s2.size();
}
Snippet 2: would this code work?
bool compare(string s1,string s2)
{
return s1.size() < s2.size();
}
The &
sign (reference) is needed, because this way the program will only use a reference to the original string. If you don't use a reference, then the program will copy the string, so the program will be
A const reference ( const string&
) is even better, because it will make it read-only, so you can pass string literals. Like compare("abc", "foo bar")
.
Yes, your second snippet would work, but it's not recommended.
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