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2349. Design a Number Container System

Description

Design a number container system that can do the following:

  • Insert or Replace a number at the given index in the system.
  • Return the smallest index for the given number in the system.

Implement the NumberContainers class:

  • NumberContainers() Initializes the number container system.
  • void change(int index, int number) Fills the container at index with the number. If there is already a number at that index, replace it.
  • int find(int number) Returns the smallest index for the given number, or -1 if there is no index that is filled by number in the system.

 

Example 1:

Input
["NumberContainers", "find", "change", "change", "change", "change", "find", "change", "find"]
[[], [10], [2, 10], [1, 10], [3, 10], [5, 10], [10], [1, 20], [10]]
Output
[null, -1, null, null, null, null, 1, null, 2]

Explanation
NumberContainers nc = new NumberContainers();
nc.find(10); // There is no index that is filled with number 10. Therefore, we return -1.
nc.change(2, 10); // Your container at index 2 will be filled with number 10.
nc.change(1, 10); // Your container at index 1 will be filled with number 10.
nc.change(3, 10); // Your container at index 3 will be filled with number 10.
nc.change(5, 10); // Your container at index 5 will be filled with number 10.
nc.find(10); // Number 10 is at the indices 1, 2, 3, and 5. Since the smallest index that is filled with 10 is 1, we return 1.
nc.change(1, 20); // Your container at index 1 will be filled with number 20. Note that index 1 was filled with 10 and then replaced with 20. 
nc.find(10); // Number 10 is at the indices 2, 3, and 5. The smallest index that is filled with 10 is 2. Therefore, we return 2.

 

Constraints:

  • 1 <= index, number <= 109
  • At most 105 calls will be made in total to change and find.

Solutions

  • class NumberContainers {
        private Map<Integer, Integer> mp = new HashMap<>();
        private Map<Integer, TreeSet<Integer>> t = 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);
                }
            }
            mp.put(index, number);
            t.computeIfAbsent(number, k -> new TreeSet<>()).add(index);
        }
    
        public int find(int number) {
            return t.containsKey(number) ? t.get(number).first() : -1;
        }
    }
    
    /**
     * Your NumberContainers object will be instantiated and called as such:
     * NumberContainers obj = new NumberContainers();
     * obj.change(index,number);
     * int param_2 = obj.find(number);
     */
    
  • 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);
        }
    
        int find(int number) {
            auto it = t.find(number);
            return it == t.end() || it->second.empty() ? -1 : *it->second.begin();
        }
    };
    
    /**
     * Your NumberContainers object will be instantiated and called as such:
     * NumberContainers* obj = new NumberContainers();
     * obj->change(index,number);
     * int param_2 = obj->find(number);
     */
    
  • from sortedcontainers import SortedSet
    
    
    class NumberContainers:
        def __init__(self):
            self.mp = {}
            self.t = 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)
    
        def find(self, number: int) -> int:
            s = self.t[number]
            return s[0] if s else -1
    
    
    # Your NumberContainers object will be instantiated and called as such:
    # obj = NumberContainers()
    # obj.change(index,number)
    # param_2 = obj.find(number)
    
    
  • type NumberContainers struct {
    	mp map[int]int
    	t  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)
    	}
    	this.mp[index] = number
    	if this.t[number] == nil {
    		this.t[number] = redblacktree.NewWithIntComparator()
    	}
    	this.t[number].Put(index, nil)
    }
    
    func (this *NumberContainers) Find(number int) int {
    	s, ok := this.t[number]
    	if !ok || s.Size() == 0 {
    		return -1
    	}
    	return s.Left().Key.(int)
    }
    
    /**
     * Your NumberContainers object will be instantiated and called as such:
     * obj := Constructor();
     * obj.Change(index,number);
     * param_2 := obj.Find(number);
     */
    
  • class NumberContainers {
        private d = new Map<number, number>();
        private g = new Map<number, TreeSet<number>>();
        constructor() {}
    
        change(index: number, number: number): void {
            if (this.d.has(index)) {
                const oldNumber = this.d.get(index)!;
                this.g.get(oldNumber)!.delete(index);
                if (!this.g.get(oldNumber)!.size()) {
                    this.g.delete(oldNumber);
                }
            }
            this.d.set(index, number);
            if (!this.g.has(number)) {
                this.g.set(number, new TreeSet());
            }
            this.g.get(number)!.add(index);
        }
    
        find(number: number): number {
            return this.g.has(number) ? this.g.get(number)!.first()! : -1;
        }
    }
    
    type Compare<T> = (lhs: T, rhs: T) => number;
    
    class RBTreeNode<T = number> {
        data: T;
        count: number;
        left: RBTreeNode<T> | null;
        right: RBTreeNode<T> | null;
        parent: RBTreeNode<T> | null;
        color: number;
        constructor(data: T) {
            this.data = data;
            this.left = this.right = this.parent = null;
            this.color = 0;
            this.count = 1;
        }
    
        sibling(): RBTreeNode<T> | null {
            if (!this.parent) return null; // sibling null if no parent
            return this.isOnLeft() ? this.parent.right : this.parent.left;
        }
    
        isOnLeft(): boolean {
            return this === this.parent!.left;
        }
    
        hasRedChild(): boolean {
            return (
                Boolean(this.left && this.left.color === 0) ||
                Boolean(this.right && this.right.color === 0)
            );
        }
    }
    
    class RBTree<T> {
        root: RBTreeNode<T> | null;
        lt: (l: T, r: T) => boolean;
        constructor(compare: Compare<T> = (l: T, r: T) => (l < r ? -1 : l > r ? 1 : 0)) {
            this.root = null;
            this.lt = (l: T, r: T) => compare(l, r) < 0;
        }
    
        rotateLeft(pt: RBTreeNode<T>): void {
            const right = pt.right!;
            pt.right = right.left;
    
            if (pt.right) pt.right.parent = pt;
            right.parent = pt.parent;
    
            if (!pt.parent) this.root = right;
            else if (pt === pt.parent.left) pt.parent.left = right;
            else pt.parent.right = right;
    
            right.left = pt;
            pt.parent = right;
        }
    
        rotateRight(pt: RBTreeNode<T>): void {
            const left = pt.left!;
            pt.left = left.right;
    
            if (pt.left) pt.left.parent = pt;
            left.parent = pt.parent;
    
            if (!pt.parent) this.root = left;
            else if (pt === pt.parent.left) pt.parent.left = left;
            else pt.parent.right = left;
    
            left.right = pt;
            pt.parent = left;
        }
    
        swapColor(p1: RBTreeNode<T>, p2: RBTreeNode<T>): void {
            const tmp = p1.color;
            p1.color = p2.color;
            p2.color = tmp;
        }
    
        swapData(p1: RBTreeNode<T>, p2: RBTreeNode<T>): void {
            const tmp = p1.data;
            p1.data = p2.data;
            p2.data = tmp;
        }
    
        fixAfterInsert(pt: RBTreeNode<T>): void {
            let parent = null;
            let grandParent = null;
    
            while (pt !== this.root && pt.color !== 1 && pt.parent?.color === 0) {
                parent = pt.parent;
                grandParent = pt.parent.parent;
    
                /*  Case : A
                    Parent of pt is left child of Grand-parent of pt */
                if (parent === grandParent?.left) {
                    const uncle = grandParent.right;
    
                    /* Case : 1
                       The uncle of pt is also red
                       Only Recoloring required */
                    if (uncle && uncle.color === 0) {
                        grandParent.color = 0;
                        parent.color = 1;
                        uncle.color = 1;
                        pt = grandParent;
                    } else {
                        /* Case : 2
                           pt is right child of its parent
                           Left-rotation required */
                        if (pt === parent.right) {
                            this.rotateLeft(parent);
                            pt = parent;
                            parent = pt.parent;
                        }
    
                        /* Case : 3
                           pt is left child of its parent
                           Right-rotation required */
                        this.rotateRight(grandParent);
                        this.swapColor(parent!, grandParent);
                        pt = parent!;
                    }
                } else {
                    /* Case : B
                   Parent of pt is right child of Grand-parent of pt */
                    const uncle = grandParent!.left;
    
                    /*  Case : 1
                        The uncle of pt is also red
                        Only Recoloring required */
                    if (uncle != null && uncle.color === 0) {
                        grandParent!.color = 0;
                        parent.color = 1;
                        uncle.color = 1;
                        pt = grandParent!;
                    } else {
                        /* Case : 2
                           pt is left child of its parent
                           Right-rotation required */
                        if (pt === parent.left) {
                            this.rotateRight(parent);
                            pt = parent;
                            parent = pt.parent;
                        }
    
                        /* Case : 3
                           pt is right child of its parent
                           Left-rotation required */
                        this.rotateLeft(grandParent!);
                        this.swapColor(parent!, grandParent!);
                        pt = parent!;
                    }
                }
            }
            this.root!.color = 1;
        }
    
        delete(val: T): boolean {
            const node = this.find(val);
            if (!node) return false;
            node.count--;
            if (!node.count) this.deleteNode(node);
            return true;
        }
    
        deleteAll(val: T): boolean {
            const node = this.find(val);
            if (!node) return false;
            this.deleteNode(node);
            return true;
        }
    
        deleteNode(v: RBTreeNode<T>): void {
            const u = BSTreplace(v);
    
            // True when u and v are both black
            const uvBlack = (u === null || u.color === 1) && v.color === 1;
            const parent = v.parent!;
    
            if (!u) {
                // u is null therefore v is leaf
                if (v === this.root) this.root = null;
                // v is root, making root null
                else {
                    if (uvBlack) {
                        // u and v both black
                        // v is leaf, fix double black at v
                        this.fixDoubleBlack(v);
                    } else {
                        // u or v is red
                        if (v.sibling()) {
                            // sibling is not null, make it red"
                            v.sibling()!.color = 0;
                        }
                    }
                    // delete v from the tree
                    if (v.isOnLeft()) parent.left = null;
                    else parent.right = null;
                }
                return;
            }
    
            if (!v.left || !v.right) {
                // v has 1 child
                if (v === this.root) {
                    // v is root, assign the value of u to v, and delete u
                    v.data = u.data;
                    v.left = v.right = null;
                } else {
                    // Detach v from tree and move u up
                    if (v.isOnLeft()) parent.left = u;
                    else parent.right = u;
                    u.parent = parent;
                    if (uvBlack) this.fixDoubleBlack(u);
                    // u and v both black, fix double black at u
                    else u.color = 1; // u or v red, color u black
                }
                return;
            }
    
            // v has 2 children, swap data with successor and recurse
            this.swapData(u, v);
            this.deleteNode(u);
    
            // find node that replaces a deleted node in BST
            function BSTreplace(x: RBTreeNode<T>): RBTreeNode<T> | null {
                // when node have 2 children
                if (x.left && x.right) return successor(x.right);
                // when leaf
                if (!x.left && !x.right) return null;
                // when single child
                return x.left ?? x.right;
            }
            // find node that do not have a left child
            // in the subtree of the given node
            function successor(x: RBTreeNode<T>): RBTreeNode<T> {
                let temp = x;
                while (temp.left) temp = temp.left;
                return temp;
            }
        }
    
        fixDoubleBlack(x: RBTreeNode<T>): void {
            if (x === this.root) return; // Reached root
    
            const sibling = x.sibling();
            const parent = x.parent!;
            if (!sibling) {
                // No sibiling, double black pushed up
                this.fixDoubleBlack(parent);
            } else {
                if (sibling.color === 0) {
                    // Sibling red
                    parent.color = 0;
                    sibling.color = 1;
                    if (sibling.isOnLeft()) this.rotateRight(parent);
                    // left case
                    else this.rotateLeft(parent); // right case
                    this.fixDoubleBlack(x);
                } else {
                    // Sibling black
                    if (sibling.hasRedChild()) {
                        // at least 1 red children
                        if (sibling.left && sibling.left.color === 0) {
                            if (sibling.isOnLeft()) {
                                // left left
                                sibling.left.color = sibling.color;
                                sibling.color = parent.color;
                                this.rotateRight(parent);
                            } else {
                                // right left
                                sibling.left.color = parent.color;
                                this.rotateRight(sibling);
                                this.rotateLeft(parent);
                            }
                        } else {
                            if (sibling.isOnLeft()) {
                                // left right
                                sibling.right!.color = parent.color;
                                this.rotateLeft(sibling);
                                this.rotateRight(parent);
                            } else {
                                // right right
                                sibling.right!.color = sibling.color;
                                sibling.color = parent.color;
                                this.rotateLeft(parent);
                            }
                        }
                        parent.color = 1;
                    } else {
                        // 2 black children
                        sibling.color = 0;
                        if (parent.color === 1) this.fixDoubleBlack(parent);
                        else parent.color = 1;
                    }
                }
            }
        }
    
        insert(data: T): boolean {
            // search for a position to insert
            let parent = this.root;
            while (parent) {
                if (this.lt(data, parent.data)) {
                    if (!parent.left) break;
                    else parent = parent.left;
                } else if (this.lt(parent.data, data)) {
                    if (!parent.right) break;
                    else parent = parent.right;
                } else break;
            }
    
            // insert node into parent
            const node = new RBTreeNode(data);
            if (!parent) this.root = node;
            else if (this.lt(node.data, parent.data)) parent.left = node;
            else if (this.lt(parent.data, node.data)) parent.right = node;
            else {
                parent.count++;
                return false;
            }
            node.parent = parent;
            this.fixAfterInsert(node);
            return true;
        }
    
        find(data: T): RBTreeNode<T> | null {
            let p = this.root;
            while (p) {
                if (this.lt(data, p.data)) {
                    p = p.left;
                } else if (this.lt(p.data, data)) {
                    p = p.right;
                } else break;
            }
            return p ?? null;
        }
    
        *inOrder(root: RBTreeNode<T> = this.root!): Generator<T, undefined, void> {
            if (!root) return;
            for (const v of this.inOrder(root.left!)) yield v;
            yield root.data;
            for (const v of this.inOrder(root.right!)) yield v;
        }
    
        *reverseInOrder(root: RBTreeNode<T> = this.root!): Generator<T, undefined, void> {
            if (!root) return;
            for (const v of this.reverseInOrder(root.right!)) yield v;
            yield root.data;
            for (const v of this.reverseInOrder(root.left!)) yield v;
        }
    }
    
    class TreeSet<T = number> {
        _size: number;
        tree: RBTree<T>;
        compare: Compare<T>;
        constructor(
            collection: T[] | Compare<T> = [],
            compare: Compare<T> = (l: T, r: T) => (l < r ? -1 : l > r ? 1 : 0),
        ) {
            if (typeof collection === 'function') {
                compare = collection;
                collection = [];
            }
            this._size = 0;
            this.compare = compare;
            this.tree = new RBTree(compare);
            for (const val of collection) this.add(val);
        }
    
        size(): number {
            return this._size;
        }
    
        has(val: T): boolean {
            return !!this.tree.find(val);
        }
    
        add(val: T): boolean {
            const successful = this.tree.insert(val);
            this._size += successful ? 1 : 0;
            return successful;
        }
    
        delete(val: T): boolean {
            const deleted = this.tree.deleteAll(val);
            this._size -= deleted ? 1 : 0;
            return deleted;
        }
    
        ceil(val: T): T | undefined {
            let p = this.tree.root;
            let higher = null;
            while (p) {
                if (this.compare(p.data, val) >= 0) {
                    higher = p;
                    p = p.left;
                } else {
                    p = p.right;
                }
            }
            return higher?.data;
        }
    
        floor(val: T): T | undefined {
            let p = this.tree.root;
            let lower = null;
            while (p) {
                if (this.compare(val, p.data) >= 0) {
                    lower = p;
                    p = p.right;
                } else {
                    p = p.left;
                }
            }
            return lower?.data;
        }
    
        higher(val: T): T | undefined {
            let p = this.tree.root;
            let higher = null;
            while (p) {
                if (this.compare(val, p.data) < 0) {
                    higher = p;
                    p = p.left;
                } else {
                    p = p.right;
                }
            }
            return higher?.data;
        }
    
        lower(val: T): T | undefined {
            let p = this.tree.root;
            let lower = null;
            while (p) {
                if (this.compare(p.data, val) < 0) {
                    lower = p;
                    p = p.right;
                } else {
                    p = p.left;
                }
            }
            return lower?.data;
        }
    
        first(): T | undefined {
            return this.tree.inOrder().next().value;
        }
    
        last(): T | undefined {
            return this.tree.reverseInOrder().next().value;
        }
    
        shift(): T | undefined {
            const first = this.first();
            if (first === undefined) return undefined;
            this.delete(first);
            return first;
        }
    
        pop(): T | undefined {
            const last = this.last();
            if (last === undefined) return undefined;
            this.delete(last);
            return last;
        }
    
        *[Symbol.iterator](): Generator<T, void, void> {
            for (const val of this.values()) yield val;
        }
    
        *keys(): Generator<T, void, void> {
            for (const val of this.values()) yield val;
        }
    
        *values(): Generator<T, undefined, void> {
            for (const val of this.tree.inOrder()) yield val;
            return undefined;
        }
    
        /**
         * Return a generator for reverse order traversing the set
         */
        *rvalues(): Generator<T, undefined, void> {
            for (const val of this.tree.reverseInOrder()) yield val;
            return undefined;
        }
    }
    
    /**
     * Your NumberContainers object will be instantiated and called as such:
     * var obj = new NumberContainers()
     * obj.change(index,number)
     * var param_2 = obj.find(number)
     */
    
    

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