what does map.count() return in c++
Explanation of map.count()
in C++
In C++, map.count()
is a member function of the std::map
container class. It is used to count the number of elements in the map that have a specific key. The function returns an integer value representing the count.
Here is an example usage of map.count()
:
#include <iostream>
#include <map>
int main() {
std::map<int, std::string> myMap;
myMap[1] = "one";
myMap[2] = "two";
myMap[3] = "three";
int key = 2;
int count = myMap.count(key);
std::cout << "The count of key " << key << " is: " << count << std::endl;
return 0;
}
In this example, myMap.count(key)
is used to count the number of elements in myMap
that have the key 2
. The result is stored in the variable count
and then printed to the console.
The output of the above code will be:
The count of key 2 is: 1
This means that there is one element in the map with the key 2
.
Please note that the count()
function returns either 0
or 1
because the keys in a std::map
are unique. If the key is present in the map, the count will be 1
; otherwise, it will be 0
.
I hope this explanation helps! Let me know if you have any further questions.