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Rust program to check the given HashMap is empty or not

Rust | HashMap Example: Write a program to check whether the given HashMap is empty or not.
Submitted by Nidhi, on October 17, 2021

Problem Solution:

In this program, we will create two HashMaps and then we will check created maps are empty or not using the is_empty() method.

Program/Source Code:

The source code to check given HashMap is empty or not is given below. The given program is compiled and executed successfully.

// Rust program to check the given 
// HashMap is empty or not

use std::collections::HashMap;

fn main() 
{
    let mut map1 = HashMap::new();
    let mut map2: HashMap<&str, i32> = [].iter().cloned().collect();
    
    map1.insert("Key1", 101);
    map1.insert("Key2", 102);
    map1.insert("Key3", 103);
    map1.insert("Key4", 104);

    if map1.is_empty()
    {
        println!("The map1 is an empty HashMap");
    }
    else
    {
        println!("The map1 is not an empty HashMap");
    }
    
    if map2.is_empty()
    {
        println!("The map2 is an empty HashMap");
    }
    else
    {
        println!("The map2 is not an empty HashMap");
    }
}

Output:

The map1 is not an empty HashMap
The map2 is an empty HashMap

Explanation:

Here, we created two HashMaps. Then we checked created HashMaps are empty or not using the is_empty() method and printed the appropriate message.

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