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Rust program to find the length of HashMap

Rust | HashMap Example: Write a program to find the length of HashMap.
Submitted by Nidhi, on October 17, 2021

Problem Solution:

In this program, we will create a HashMap and then we will insert items into HashMap using the insert() function. After that, we will find the length of HashMap using the len() method and print HashMap.

Program/Source Code:

The source code to find the length of HashMap is given below. The given program is compiled and executed successfully.

// Rust program to find the length of HashMap

use std::collections::HashMap;

fn main() 
{
    let mut map = HashMap::new();
    
    map.insert("Key1", 101);
    map.insert("Key2", 102);
    map.insert("Key3", 103);
    map.insert("Key4", 104);

    println!("Length of HashMap: {}\n",map.len());
    
    println!("HashMap Keys/values:");
    for (key, val) in map.iter() {
        println!("{} -> {}", key, val);
    }
}

Output:

Length of HashMap: 4

HashMap Keys/values:
Key2 -> 102
Key3 -> 103
Key1 -> 101
Key4 -> 104

Explanation:

Here, we created a HashMap. Then we inserted the item into HashMap and find the length of HashMap using the len() method and printed the HashMap.

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