Example: FrequencyCount_HashMap in C++

C
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Java
Python
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// FrequencyCount_HashMap
#include <iostream>
#include <vector>
#include <map> // For std::map

int main() {
    // Step 1: Initialize the array
    std::vector<int> arr = {5, 2, 8, 5, 1, 2, 5};

    // Step 2: Create a std::map to store element frequencies
    // Keys will be array elements, values will be their counts
    std::map<int, int> frequencies;

    // Step 3: Iterate through the array and populate the map
    for (int element : arr) {
        frequencies[element]++; // Increments count for existing key, or inserts new key with count 1
    }

    std::cout << "Element frequencies using Hash Map (std::map):" << std::endl;

    // Step 4: Iterate through the map and print key-value pairs
    // std::map iterates in sorted key order
    for (const auto& pair : frequencies) {
        std::cout << "Element " << pair.first << ": " << pair.second << " time(s)" << std::endl;
    }

    return 0;
}