feat: add solutions to lc problem: No.2349 (#3312)

Author: yanglbme

solution/2300-2399/2349.Design a Number Container System/README.md

@@ -1,25 +1,27 @@
 class NumberContainers {
 public:
-    map<int, int> mp;
-    map<int, set<int>> t;
-
     NumberContainers() {
     }
 
     void change(int index, int number) {
-        auto it = mp.find(index);
-        if (it != mp.end()) {
-            t[it->second].erase(index);
-            it->second = number;
-        } else
-            mp[index] = number;
-        t[number].insert(index);
+        if (d.contains(index)) {
+            int oldNumber = d[index];
+            g[oldNumber].erase(index);
+            if (g[oldNumber].empty()) {
+                g.erase(oldNumber);
+            }
+        }
+        d[index] = number;
+        g[number].insert(index);
     }
 
     int find(int number) {
-        auto it = t.find(number);
-        return it == t.end() || it->second.empty() ? -1 : *it->second.begin();
+        return g.contains(number) ? *g[number].begin() : -1;
     }
+
+private:
+    unordered_map<int, int> d;
+    unordered_map<int, set<int>> g;
 };
 
 /**

solution/2300-2399/2349.Design a Number Container System/README_EN.md

@@ -1,29 +1,28 @@
 type NumberContainers struct {
-	mp map[int]int
-	t  map[int]*redblacktree.Tree
+	d map[int]int
+	g map[int]*redblacktree.Tree
 }
 
 func Constructor() NumberContainers {
 	return NumberContainers{map[int]int{}, map[int]*redblacktree.Tree{}}
 }
 
 func (this *NumberContainers) Change(index int, number int) {
-	if num, ok := this.mp[index]; ok {
-		this.t[num].Remove(index)
+	if oldNumber, ok := this.d[index]; ok {
+		this.g[oldNumber].Remove(index)
 	}
-	this.mp[index] = number
-	if this.t[number] == nil {
-		this.t[number] = redblacktree.NewWithIntComparator()
+	this.d[index] = number
+	if _, ok := this.g[number]; !ok {
+		this.g[number] = redblacktree.NewWithIntComparator()
 	}
-	this.t[number].Put(index, nil)
+	this.g[number].Put(index, nil)
 }
 
 func (this *NumberContainers) Find(number int) int {
-	s, ok := this.t[number]
-	if !ok || s.Size() == 0 {
-		return -1
+	if ids, ok := this.g[number]; ok && ids.Size() > 0 {
+		return ids.Left().Key.(int)
 	}
-	return s.Left().Key.(int)
+	return -1
 }
 
 /**

solution/2300-2399/2349.Design a Number Container System/Solution.cpp

@@ -1,24 +1,22 @@
 class NumberContainers {
-    private Map<Integer, Integer> mp = new HashMap<>();
-    private Map<Integer, TreeSet<Integer>> t = new HashMap<>();
+    private Map<Integer, Integer> d = new HashMap<>();
+    private Map<Integer, TreeSet<Integer>> g = new HashMap<>();
 
     public NumberContainers() {
     }
 
     public void change(int index, int number) {
-        if (mp.containsKey(index)) {
-            int v = mp.get(index);
-            t.get(v).remove(index);
-            if (t.get(v).isEmpty()) {
-                t.remove(v);
-            }
+        if (d.containsKey(index)) {
+            int oldNumber = d.get(index);
+            g.get(oldNumber).remove(index);
         }
-        mp.put(index, number);
-        t.computeIfAbsent(number, k -> new TreeSet<>()).add(index);
+        d.put(index, number);
+        g.computeIfAbsent(number, k -> new TreeSet<>()).add(index);
     }
 
     public int find(int number) {
-        return t.containsKey(number) ? t.get(number).first() : -1;
+        var ids = g.get(number);
+        return ids == null || ids.isEmpty() ? -1 : ids.first();
     }
 }
 

solution/2300-2399/2349.Design a Number Container System/Solution.go

@@ -2,20 +2,21 @@
 
 
 class NumberContainers:
+
     def __init__(self):
-        self.mp = {}
-        self.t = defaultdict(SortedSet)
+        self.d = {}
+        self.g = defaultdict(SortedSet)
 
     def change(self, index: int, number: int) -> None:
-        if index in self.mp:
-            v = self.mp[index]
-            self.t[v].remove(index)
-        self.mp[index] = number
-        self.t[number].add(index)
+        if index in self.d:
+            old_number = self.d[index]
+            self.g[old_number].remove(index)
+        self.d[index] = number
+        self.g[number].add(index)
 
     def find(self, number: int) -> int:
-        s = self.t[number]
-        return s[0] if s else -1
+        ids = self.g[number]
+        return ids[0] if ids else -1
 
 
 # Your NumberContainers object will be instantiated and called as such: