find the symmetric difference of two maps in rust

To find the symmetric difference of two maps in Rust, we can first get the set of keys that are present in either of the two maps using the HashSet datatype. We then use a loop to iterate over this set of keys and find the values for each key in the two maps. We can then add the values that are present in only one of the maps to the result map. Here's an example implementation:

main.rs
use std::collections::{HashMap, HashSet};

fn symmetric_difference<K, V>(map1: &HashMap<K, V>, map2: &HashMap<K, V>) -> HashMap<&K, &V> {
    let mut result = HashMap::new();
    let mut keys = HashSet::new();

    // Get the set of keys that are present in either of the two maps
    for key in map1.keys() {
        keys.insert(key);
    }
    for key in map2.keys() {
        keys.insert(key);
    }

    // Find the values for each key in the two maps
    for key in keys {
        let val1 = map1.get(key);
        let val2 = map2.get(key);

        // Add the values that are present in only one of the maps to the result map
        match (val1, val2) {
            (None, Some(val)) => {
                result.insert(key, val);
            }
            (Some(val), None) => {
                result.insert(key, val);
            }
            _ => (),
        }
    }

    result
}
892 chars
34 lines

Here, we create a new HashMap called result to hold the values present in only one of the maps. We also create a HashSet called keys to hold the set of keys that are present in either of the two maps.

We then iterate over the keys in both maps and check if each key is present in only one of the maps. If a key is present in one map but not the other, we add it to the result map along with its value.

This implementation assumes that both maps have the same key-value types. If they are different, you would need to modify the implementation accordingly.