#include <iostream>
#include <unordered_map>
int main() {
// Step 1: Declare an unordered_map
std::unordered_map<int, std::string> myMap;
// Step 2: Insert key-value pairs into the unordered_map
myMap.insert({1, "One"});
myMap.insert({2, "Two"});
myMap[3] = "Three";
// Step 3: Access elements using keys
std::cout << "Value at key 2: " << myMap[2] << std::endl;
// Step 4: Check if a key exists in the unordered_map
if (myMap.find(3) != myMap.end()) {
std::cout << "Key 3 found. Value: " << myMap[3] << std::endl;
} else {
std::cout << "Key 3 not found." << std::endl;
}
// Step 5: Iterate through the unordered_map
for (const auto& pair : myMap) {
std::cout << "Key: " << pair.first << ", Value: " << pair.second << std::endl;
}
// Step 6: Erase an element by key
myMap.erase(2);
// Step 7: Check if the unordered_map is empty
if (myMap.empty()) {
std::cout << "The unordered_map is empty." << std::endl;
} else {
std::cout << "The unordered_map is not empty." << std::endl;
}
return 0;
}