rustHow to get the first value from a Rust HashMap?

The first value from a Rust HashMap can be obtained using the get method. This method takes a reference to the key and returns an Option<&V> where V is the type of the value associated with the key.

Example code

use std::collections::HashMap;

let mut map = HashMap::new();
map.insert("key1", "value1");
map.insert("key2", "value2");

let first_value = map.get("key1");

Output example

Some("value1")

Code explanation

• use std::collections::HashMap: imports the HashMap type from the std::collections module.
• let mut map = HashMap::new(): creates a new empty HashMap instance.
• map.insert("key1", "value1"): inserts a key-value pair into the HashMap.
• let first_value = map.get("key1"): gets the value associated with the key "key1" from the HashMap.

Helpful links

• Rust HashMap documentation

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