I have a List of object sorted and I want to find the first occurrence and the last occurrence of an object. In C++, I can easily use std::equal_range (or just one lower_bound and one upper_bound).
For example:
bool mygreater (int i,int j) { return (i>j); }
int main () {
int myints[] = {10,20,30,30,20,10,10,20};
std::vector<int> v(myints,myints+8); // 10 20 30 30 20 10 10 20
std::pair<std::vector<int>::iterator,std::vector<int>::iterator> bounds;
// using default comparison:
std::sort (v.begin(), v.end()); // 10 10 10 20 20 20 30 30
bounds=std::equal_range (v.begin(), v.end(), 20); // ^ ^
// using "mygreater" as comp:
std::sort (v.begin(), v.end(), mygreater); // 30 30 20 20 20 10 10 10
bounds=std::equal_range (v.begin(), v.end(), 20, mygreater); // ^ ^
std::cout << "bounds at positions " << (bounds.first - v.begin());
std::cout << " and " << (bounds.second - v.begin()) << '
';
return 0;
}
In Java, there seems to be no simple equivalence? How should I do with the equal range with
List<MyClass> myList;
By the way, I am using a standard import java.util.List;
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