Category: std::map
How to search by value in a Map | C++
In this article will discuss how to search for all the elements in map with given value. Map internally store elements in Key-Value pair. In which keys are unique but values can be duplicate. There are member functions to search pairs by key i.e. std::map::find(). But there is no direct function to search for all …
C++ map : Erase element by key or Iterator or Range
In this article we will discuss the different ways to delete a key-value pair from map. std::map provides 3 overloaded version of erase() to remove elements from map i.e. Advertisements Erase by key Erase by Iterator Erase a range Lets discuss them one by one, Erase Element from Map by Key std::map provides a erase function that accepts …
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C++ Map: Erase by Value or Callback while iterating | erase_if for map
In this article we will discuss two different ways to erase elements from map i.e. In previous article we discussed how to erase elements by key and iterator using member function std::map::erase. But there is no default function to delete elements by value instead of key or delete elements based on callback. Advertisements We will …
C++ Map: Erase by Value or Callback while iterating | erase_if for mapRead More
C++ Map : Operator [] – Usage Details
In this article we will discuss how to use operator [] with map in C++. std::map has Operator[] i.e. Advertisements mapped_type& operator[] (const key_type& k); operator [] works in Find or Create Mode i.e. when called with a key K, it will try to look for element with given key K and can go in …
map vs unordered_map | When to choose one over another ?
In this article we will compare std::map and std::unordered_map and will also discuss when to choose one over another. Both std::map & std::unordered_map store elements in key value pair & provide member functions to efficiently insert, search & delete key value pairs. Advertisements But they are different in following areas, Internal Implementation Memory Usage Time …
map vs unordered_map | When to choose one over another ?Read More
How to copy all Values from a Map to a Vector in C++
In this article we will discuss how to fetch all values from a map and put them in vector. Suppose we have a map of words and their frequency count i.e. Advertisements // Map of string & int // To store the frequency count of words std::map<std::string, int> wordMap = { { “is”, 6 }, …
How to copy all Values from a Map to a Vector in C++Read More