unordered_map empty in C++ STL

unordered_map::empty() function is used to check whether container size is zero or not. If container size is zero then it return TRUE otherwise it return FALSE.
Syntax:

 unordered_map_name.empty()

Parameters: This function does not accept any parameter
Return type: This function returns boolean value TRUE or FALSE.

Examples:

Input: ump = { {1, 2}, {3, 4}, {5, 6}, {7, 8}}
ump.empty();
Output: False

Input: ump = { };
ump.empty();
Output: True

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// CPP program to illustrate
// Implementation of unordered_map empty() function
#include <bits/stdc++.h>
using namespace std;
  
int main()
{
    // Take any two unordered_map
    unordered_map<int, int> ump1, ump2;
  
    // Inserting values
    ump1[1] = 2;
    ump1[3] = 4;
    ump1[5] = 6;
    ump1[7] = 8;
  
    // Print the size of container
    cout << "ump1 size = " << ump1.size() << endl;
    cout << "ump2 size = " << ump2.size() << endl;
  
    // Running the function for ump1
    if (ump1.empty())
        cout << "True\n";
    else
        cout << "False\n";
  
    // Running the function for ump2
    if (ump2.empty())
        cout << "True\n";
    else
        cout << "False\n";
  
    // Running the function for ump1 after
    // clearing it
    ump1.clear();
    if (ump1.empty())
        cout << "True\n";
    else
        cout << "False\n";
  
    return 0;
}

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Output:

ump1 size = 4
ump2 size = 0
False
True
True


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