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finish hash maps

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Reality Enjoyer
2026-01-14 07:25:19 +00:00
parent d76140e0c9
commit 25da030d2f
1 changed files with 9 additions and 33 deletions
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42
average_speed/src/main.rs
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@@ -39,42 +39,18 @@ fn main() {
println!("\nDEBUG: updating their values..."); println!("\nDEBUG: updating their values...");
println!("\tvalues before updating:\n\t{runners:?}"); println!("\tvalues before updating:\n\t{runners:?}");
// can be improved using hash maps // updating values using another hash map
let val = vec![4, 10, 8, 9]; let mut new_values = HashMap::new();
let names = ["Jill", "Jack", "Jane", "Joe"];
let mut count = 0; new_values.entry(jane.clone()).or_insert(8);
new_values.entry(jill.clone()).or_insert(4);
new_values.entry(jack.clone()).or_insert(10);
new_values.entry(joe.clone()).or_insert(9);
for n in names { for (key, val) in new_values.iter() {
let tmp = n.to_string(); let updater = runners.entry(key.clone()).or_insert(0);
let updater = runners.entry(tmp.clone()).or_insert(0); *updater = (*updater + val) / 2;
*updater += val[count];
*updater /= 2;
count += 1;
} }
println!("\n\tvalues after updating:\n\t{runners:?}"); println!("\n\tvalues after updating:\n\t{runners:?}");
} }
/* figuring out how to update values
println!("Jill's average before: {:?}", runners.get(&jill).unwrap());
let curr_value = runners.get(&jill).unwrap();
println!("\t{curr_value}");
let new_value = 4;
println!("\t{new_value}");
let final_value = (curr_value + new_value) / 2;
println!("\t{final_value}");
runners.insert(jill.clone(), final_value);
let updater = runners.entry(jill.clone()).or_insert(0);
*updater += new_value;
*updater /= 2;
println!("Jill's average after: {:?}", runners.get(&jill).unwrap());
*/