Rust HashMap: Inserting Name-Age pairs

Last update on December 21 2024 10:21:33 (UTC/GMT +8 hours)

Write a Rust program that creates an empty HashMap and inserts key-value pairs representing the names and ages of people.

Sample Solution:

Rust Code:

use std::collections::HashMap; // Import the HashMap type from the standard library

fn main() {
    // Create an empty HashMap to store names and ages of people
    let mut people: HashMap<String, u32> = HashMap::new(); // Key: String (name), Value: u32 (age)

    // Insert key-value pairs representing names and ages of people into the HashMap
    people.insert(String::from("Lennart"), 40);  
    people.insert(String::from("Nagendra"), 51);  
    people.insert(String::from("Adino"), 35);  

    // Print the HashMap containing names and ages of people
    println!("People: {:?}", people);
}

Output:

People: {"Lennart": 40, "Nagendra": 51, "Adino": 35}

Explanation:

Here is a brief explanation of the above Rust code:

• use std::collections::HashMap;: This line imports the HashMap type from the standard library's collections module, allowing the use of HashMaps in the code.
• fn main() { ... }: This line defines the main function, which serves as the entry point of the Rust program.
• let mut people: HashMap<String, u32> = HashMap::new();: This line declares a mutable variable named 'people' and initializes it as an empty HashMap. The HashMap is defined to have keys of type "String" (representing names) and values of type u32 (representing ages).
• people.insert(String::from("Lennart"), 40);: This line inserts a key-value pair into the people HashMap, where the key is the String "Lennart" (representing a person's name) and the value is the u32 40 (representing Lennart's age). Similar lines insert additional key-value pairs for other people's names and ages.
• println!("People: {:?}", people);: This line prints the content of the 'people' HashMap, including all the inserted names and ages, using debug formatting. The {:?} format specifier prints the HashMap, showing its internal structure

Rust Code Editor:

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