Using STL hash tables to store data

The biggest difference between a map and a hash table is that while the map data structure is ordered, a hash table is unordered. Both use the same principle of key/value pairs. The worst case search complexity for an unordered map is O(N), as it is not ordered like a map, which has a complexity of O(log N).

Getting ready

For this recipe, you will need a Windows machine with a working copy of Visual Studio.

How to do it…

In this recipe, we will see how we can easily use the inbuilt template library provided for us by C++ to create complex data structures. After the complex data structure has been created, we can easily use it to store data and access it:

1. Open Visual Studio.

2. Create a new C++ project.

3. Add a source file called Source.cpp.

4. Add the following lines of code to it:

   #include <unordered_map>
   #include <string>
   #include <iostream>
   #include <conio.h>
   
   using namespace std;
   
   
   int main()
   {
     unordered_map<string, string> hashtable...