How do I insert and erase elements efficiently with std::unordered_map?

Efficiently managing elements in an `std::unordered_map` in C++ is crucial for performance-intensive applications. The `std::unordered_map` provides average constant time complexity for insertions and deletions, making it ideal for dynamic key-value pairs. Below is a concise example of how to insert and erase elements in an `unordered_map`.

#include <iostream> #include <unordered_map> int main() { std::unordered_map myMap; // Inserting elements myMap.insert({1, "Apple"}); myMap[2] = "Banana"; // Another way to insert // Erasing an element myMap.erase(1); // Remove the element with key 1 // Display the elements for (const auto &pair : myMap) { std::cout << pair.first << ": " << pair.second << std::endl; } return 0; }

std::unordered_map C++ hash table insert erase key-value pairs

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