How do I use iterators with std::unordered_map in C++?

Can you explain how to use iterators with std::unordered_map in C++?

Sure! In C++, std::unordered_map provides iterators to traverse its elements. You can use both begin() and end() methods to get the start and end of the map.

What does the iterator return when I dereference it?

When you dereference an iterator of std::unordered_map, it returns a std::pair<const KeyType, ValueType>, where the first element is the key and the second is the value.

Can you show me a code example?

Absolutely! Here's a simple example:

#include <iostream>
#include <unordered_map>

int main() {
    std::unordered_map<int, std::string> myMap = {{1, "one"}, {2, "two"}, {3, "three"}};
    for (auto it = myMap.begin(); it != myMap.end(); ++it) {
        std::cout << it->first << ": " << it->second << std::endl;
    }
    return 0;
}

What if I want to remove an element while iterating?

You can use the erase method. However, you should be careful to increment the iterator before erasing, or use the return value of erase to continue iterating safely.