map Size in C++

In C++, there are multiple ways to get the size of a hash. One common way is to use the size() function of the unordered_map container, which returns the number of key-value pairs in the hash table. Here is an example:

``c++ #include #include


int main() {

    std::unordered_map myHash = {{"apple", 3}, {"banana", 2}, {"cherry", 5}};

    

    std::cout << "Size of myHash is " << myHash.size() << std::endl;

    

    return 0;

}



Output:



Size of myHash is 3



Alternatively, we can use the bucket_count() function to get the number of buckets in the hash table. This value is not necessarily equal to the number of key-value pairs. Here is an example:
c++

#include 

#include 
int main() {

    std::unordered_map myHash = {{"apple", 3}, {"banana", 2}, {"cherry", 5}};

    

    std::cout << "Number of buckets in myHash is " << myHash.bucket_count() << std::endl;

    

    return 0;

}



Output:



Number of buckets in myHash is 8

Note that the number of buckets is implementation specific and may differ between different compilers or machines.

map Size in C++

See this concept in other languages