add certified btree set, add get_random 1

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "ic-stable-memory"
-version = "0.4.3"
+version = "0.4.4"
 authors = ["Александр Втюрин <[email protected]>"]
 edition = "2021"
 description = "Internet Computer's stable memory collections and tools"
@@ -24,7 +24,7 @@ ic-stable-memory-derive = "0.4.2"
 [dev-dependencies]
 rand = "0.8.5"
 ic-cdk-macros = "0.6.8"
-candid_derive = "0.5.0"
+candid_derive = "0.6.0"
 ic-certified-map = "0.3.2"
 serde_test = "1.0.152"
 

src/collections/btree_map/mod.rs

@@ -1742,8 +1742,10 @@ impl LeveledList {
         match self {
             LeveledList::None => {}
             LeveledList::Some((v, _)) => {
-                if let Ok(idx) = v[level].binary_search(&ptr) {
-                    v[level].remove(idx);
+                if let Some(level_list) = v.get_mut(level) {
+                    if let Ok(idx) = level_list.binary_search(&ptr) {
+                        level_list.remove(idx);
+                    }
                 }
             }
         }
@@ -1753,7 +1755,8 @@ impl LeveledList {
         match self {
             LeveledList::None => unreachable!(),
             LeveledList::Some((v, max_level)) => {
-                let mut ptr = v[*max_level].pop();
+                let level_list = v.get_mut(*max_level)?;
+                let mut ptr = level_list.pop();
 
                 while ptr.is_none() {
                     if *max_level == 0 {