From c2dc5aa9148e0005d9edecb8a2512589c57b300e Mon Sep 17 00:00:00 2001 From: Revone Date: Thu, 23 Jan 2025 19:12:20 +1300 Subject: [PATCH] feat: Use Number.MAX_SAFE_INTEGER instead of Infinity. --- package.json | 4 +- src/data-structures/graph/abstract-graph.ts | 28 +++--- .../graph/directed-graph.test.ts | 74 +++++++-------- .../graph/undirected-graph.test.ts | 4 +- .../linked-list/singly-linked-list.test.ts | 92 ++++++++++++++++++- 5 files changed, 146 insertions(+), 56 deletions(-) diff --git a/package.json b/package.json index 8e197bf..593f127 100644 --- a/package.json +++ b/package.json @@ -1,7 +1,7 @@ { "name": "data-structure-typed", - "version": "2.0.0", - "description": "Javascript Data Structure. Heap, Binary Tree, Red Black Tree, Linked List, Deque, Trie, HashMap, Directed Graph, Undirected Graph, Binary Search Tree(BST), AVL Tree, Priority Queue, Graph, Queue, Tree Multiset, Singly Linked List, Doubly Linked List, Max Heap, Max Priority Queue, Min Heap, Min Priority Queue, Stack. Benchmark compared with C++ STL. API aligned with ES6 and Java.util. Usability is comparable to Python", + "version": "2.0.1", + "description": "Standard data structure", "main": "dist/cjs/index.js", "module": "dist/esm/index.js", "browser": "dist/umd/data-structure-typed.min.js", diff --git a/src/data-structures/graph/abstract-graph.ts b/src/data-structures/graph/abstract-graph.ts index 7145e3d..ac40f55 100644 --- a/src/data-structures/graph/abstract-graph.ts +++ b/src/data-structures/graph/abstract-graph.ts @@ -339,7 +339,7 @@ export abstract class AbstractGraph< if (isWeight) { const allPaths = this.getAllPathsBetween(v1, v2); - let min = Infinity; + let min = Number.MAX_SAFE_INTEGER; for (const path of allPaths) { min = Math.min(this.getPathSumWeight(path), min); } @@ -404,7 +404,7 @@ export abstract class AbstractGraph< if (isWeight) { if (isDFS) { const allPaths = this.getAllPathsBetween(v1, v2, 10000); - let min = Infinity; + let min = Number.MAX_SAFE_INTEGER; let minIndex = -1; let index = 0; for (const path of allPaths) { @@ -475,7 +475,7 @@ export abstract class AbstractGraph< getMinDist: boolean = false, genPaths: boolean = false ): DijkstraResult { - let minDist = Infinity; + let minDist = Number.MAX_SAFE_INTEGER; let minDest: VO | undefined = undefined; let minPath: VO[] = []; const paths: VO[][] = []; @@ -494,13 +494,13 @@ export abstract class AbstractGraph< for (const vertex of vertexMap) { const vertexOrKey = vertex[1]; - if (vertexOrKey instanceof AbstractVertex) distMap.set(vertexOrKey, Infinity); + if (vertexOrKey instanceof AbstractVertex) distMap.set(vertexOrKey, Number.MAX_SAFE_INTEGER); } distMap.set(srcVertex, 0); preMap.set(srcVertex, undefined); const getMinOfNoSeen = () => { - let min = Infinity; + let min = Number.MAX_SAFE_INTEGER; let minV: VO | undefined = undefined; for (const [key, value] of distMap) { if (!seen.has(key)) { @@ -537,7 +537,7 @@ export abstract class AbstractGraph< seen.add(cur); if (destVertex && destVertex === cur) { if (getMinDist) { - minDist = distMap.get(destVertex) || Infinity; + minDist = distMap.get(destVertex) || Number.MAX_SAFE_INTEGER; } if (genPaths) { getPaths(destVertex); @@ -605,7 +605,7 @@ export abstract class AbstractGraph< getMinDist: boolean = false, genPaths: boolean = false ): DijkstraResult { - let minDist = Infinity; + let minDist = Number.MAX_SAFE_INTEGER; let minDest: VO | undefined = undefined; let minPath: VO[] = []; const paths: VO[][] = []; @@ -621,7 +621,7 @@ export abstract class AbstractGraph< for (const vertex of vertexMap) { const vertexOrKey = vertex[1]; - if (vertexOrKey instanceof AbstractVertex) distMap.set(vertexOrKey, Infinity); + if (vertexOrKey instanceof AbstractVertex) distMap.set(vertexOrKey, Number.MAX_SAFE_INTEGER); } const heap = new Heap<{ key: number; value: VO }>([], { comparator: (a, b) => a.key - b.key }); @@ -661,7 +661,7 @@ export abstract class AbstractGraph< seen.add(cur); if (destVertex && destVertex === cur) { if (getMinDist) { - minDist = distMap.get(destVertex) || Infinity; + minDist = distMap.get(destVertex) || Number.MAX_SAFE_INTEGER; } if (genPaths) { getPaths(destVertex); @@ -732,7 +732,7 @@ export abstract class AbstractGraph< const paths: VO[][] = []; const distMap: Map = new Map(); const preMap: Map = new Map(); // predecessor - let min = Infinity; + let min = Number.MAX_SAFE_INTEGER; let minPath: VO[] = []; // TODO let hasNegativeCycle: boolean | undefined; @@ -745,7 +745,7 @@ export abstract class AbstractGraph< const numOfEdges = edgeMap.length; this._vertexMap.forEach(vertex => { - distMap.set(vertex, Infinity); + distMap.set(vertex, Number.MAX_SAFE_INTEGER); }); distMap.set(srcVertex, 0); @@ -759,7 +759,7 @@ export abstract class AbstractGraph< const sWeight = distMap.get(s); const dWeight = distMap.get(d); if (sWeight !== undefined && dWeight !== undefined) { - if (distMap.get(s) !== Infinity && sWeight + weight < dWeight) { + if (distMap.get(s) !== Number.MAX_SAFE_INTEGER && sWeight + weight < dWeight) { distMap.set(d, sWeight + weight); if (genPath) preMap.set(d, s); } @@ -804,7 +804,7 @@ export abstract class AbstractGraph< const weight = edgeMap[j].weight; const sWeight = distMap.get(s); if (sWeight) { - if (sWeight !== Infinity && sWeight + weight < sWeight) hasNegativeCycle = true; + if (sWeight !== Number.MAX_SAFE_INTEGER && sWeight + weight < sWeight) hasNegativeCycle = true; } } } @@ -860,7 +860,7 @@ export abstract class AbstractGraph< for (let i = 0; i < n; i++) { for (let j = 0; j < n; j++) { - costs[i][j] = this.getEdge(idAndVertices[i][1], idAndVertices[j][1])?.weight || Infinity; + costs[i][j] = this.getEdge(idAndVertices[i][1], idAndVertices[j][1])?.weight || Number.MAX_SAFE_INTEGER; } } diff --git a/test/unit/data-structures/graph/directed-graph.test.ts b/test/unit/data-structures/graph/directed-graph.test.ts index a7780b4..4b1d998 100644 --- a/test/unit/data-structures/graph/directed-graph.test.ts +++ b/test/unit/data-structures/graph/directed-graph.test.ts @@ -341,9 +341,9 @@ describe('Inherit from DirectedGraph and perform operations test2.', () => { expect(distMap.get(vertex3)).toBe(35); expect(distMap.get(vertex4)).toBe(14); expect(distMap.get(vertex5)).toBe(70); - expect(distMap.get(vertex6)).toBe(Infinity); + expect(distMap.get(vertex6)).toBe(Number.MAX_SAFE_INTEGER); expect(distMap.get(vertex7)).toBe(61); - expect(distMap.get(vertex8)).toBe(Infinity); + expect(distMap.get(vertex8)).toBe(Number.MAX_SAFE_INTEGER); expect(distMap.get(vertex9)).toBe(19); expect(preMap).toBeInstanceOf(Map); @@ -351,7 +351,7 @@ describe('Inherit from DirectedGraph and perform operations test2.', () => { expect(paths).toBeInstanceOf(Array); expect(paths.length).toBe(0); - expect(min).toBe(Infinity); + expect(min).toBe(Number.MAX_SAFE_INTEGER); expect(minPath).toBeInstanceOf(Array); const floydResult = myGraph.floydWarshall(); @@ -360,35 +360,35 @@ describe('Inherit from DirectedGraph and perform operations test2.', () => { const { costs, predecessor } = floydResult; expect(costs).toBeInstanceOf(Array); expect(costs.length).toBe(9); - expect(costs[0]).toEqual([32, 12, 35, 14, 70, Infinity, 61, Infinity, 19]); - expect(costs[1]).toEqual([20, 32, 23, 34, 58, Infinity, 81, Infinity, 39]); - expect(costs[2]).toEqual([3, 15, 38, 17, 35, Infinity, 64, Infinity, 22]); - expect(costs[3]).toEqual([123, 135, 120, 137, 155, Infinity, 47, Infinity, 126]); - expect(costs[4]).toEqual([133, 145, 130, 147, 165, Infinity, 57, Infinity, 136]); + expect(costs[0]).toEqual([32, 12, 35, 14, 70, Number.MAX_SAFE_INTEGER, 61, Number.MAX_SAFE_INTEGER, 19]); + expect(costs[1]).toEqual([20, 32, 23, 34, 58, Number.MAX_SAFE_INTEGER, 81, Number.MAX_SAFE_INTEGER, 39]); + expect(costs[2]).toEqual([3, 15, 38, 17, 35, Number.MAX_SAFE_INTEGER, 64, Number.MAX_SAFE_INTEGER, 22]); + expect(costs[3]).toEqual([123, 135, 120, 137, 155, Number.MAX_SAFE_INTEGER, 47, Number.MAX_SAFE_INTEGER, 126]); + expect(costs[4]).toEqual([133, 145, 130, 147, 165, Number.MAX_SAFE_INTEGER, 57, Number.MAX_SAFE_INTEGER, 136]); expect(costs[5]).toEqual([ - Infinity, - Infinity, - Infinity, - Infinity, - Infinity, - Infinity, - Infinity, - Infinity, - Infinity + Number.MAX_SAFE_INTEGER, + Number.MAX_SAFE_INTEGER, + Number.MAX_SAFE_INTEGER, + Number.MAX_SAFE_INTEGER, + Number.MAX_SAFE_INTEGER, + Number.MAX_SAFE_INTEGER, + Number.MAX_SAFE_INTEGER, + Number.MAX_SAFE_INTEGER, + Number.MAX_SAFE_INTEGER ]); - expect(costs[6]).toEqual([76, 88, 73, 90, 108, Infinity, 137, Infinity, 79]); + expect(costs[6]).toEqual([76, 88, 73, 90, 108, Number.MAX_SAFE_INTEGER, 137, Number.MAX_SAFE_INTEGER, 79]); expect(costs[7]).toEqual([ - Infinity, - Infinity, - Infinity, - Infinity, - Infinity, - Infinity, - Infinity, - Infinity, - Infinity + Number.MAX_SAFE_INTEGER, + Number.MAX_SAFE_INTEGER, + Number.MAX_SAFE_INTEGER, + Number.MAX_SAFE_INTEGER, + Number.MAX_SAFE_INTEGER, + Number.MAX_SAFE_INTEGER, + Number.MAX_SAFE_INTEGER, + Number.MAX_SAFE_INTEGER, + Number.MAX_SAFE_INTEGER ]); - expect(costs[8]).toEqual([173, 185, 170, 187, 205, Infinity, 97, Infinity, 176]); + expect(costs[8]).toEqual([173, 185, 170, 187, 205, Number.MAX_SAFE_INTEGER, 97, Number.MAX_SAFE_INTEGER, 176]); expect(predecessor).toBeInstanceOf(Array); expect(predecessor.length).toBe(9); @@ -458,12 +458,12 @@ describe('Inherit from DirectedGraph and perform operations test2.', () => { expect(distMap.size).toBe(9); expect(distMap.get(vertex1)).toBe(0); expect(distMap.get(vertex2)).toBe(12); - expect(distMap.get(vertex3)).toBe(Infinity); + expect(distMap.get(vertex3)).toBe(Number.MAX_SAFE_INTEGER); expect(distMap.get(vertex4)).toBe(14); - expect(distMap.get(vertex5)).toBe(Infinity); - expect(distMap.get(vertex6)).toBe(Infinity); - expect(distMap.get(vertex7)).toBe(Infinity); - expect(distMap.get(vertex8)).toBe(Infinity); + expect(distMap.get(vertex5)).toBe(Number.MAX_SAFE_INTEGER); + expect(distMap.get(vertex6)).toBe(Number.MAX_SAFE_INTEGER); + expect(distMap.get(vertex7)).toBe(Number.MAX_SAFE_INTEGER); + expect(distMap.get(vertex8)).toBe(Number.MAX_SAFE_INTEGER); expect(distMap.get(vertex9)).toBe(19); expect(minDist).toBe(12); @@ -512,9 +512,9 @@ describe('Inherit from DirectedGraph and perform operations test2.', () => { expect(distMap.get(vertex3)).toBe(35); expect(distMap.get(vertex4)).toBe(14); expect(distMap.get(vertex5)).toBe(70); - expect(distMap.get(vertex6)).toBe(Infinity); + expect(distMap.get(vertex6)).toBe(Number.MAX_SAFE_INTEGER); expect(distMap.get(vertex7)).toBe(61); - expect(distMap.get(vertex8)).toBe(Infinity); + expect(distMap.get(vertex8)).toBe(Number.MAX_SAFE_INTEGER); expect(distMap.get(vertex9)).toBe(19); expect(minDist).toBe(12); @@ -574,9 +574,9 @@ describe('Inherit from DirectedGraph and perform operations test2.', () => { expect(distMap.get(vertex3)).toBe(35); expect(distMap.get(vertex4)).toBe(14); expect(distMap.get(vertex5)).toBe(70); - expect(distMap.get(vertex6)).toBe(Infinity); + expect(distMap.get(vertex6)).toBe(Number.MAX_SAFE_INTEGER); expect(distMap.get(vertex7)).toBe(61); - expect(distMap.get(vertex8)).toBe(Infinity); + expect(distMap.get(vertex8)).toBe(Number.MAX_SAFE_INTEGER); expect(distMap.get(vertex9)).toBe(19); expect(minDist).toBe(12); diff --git a/test/unit/data-structures/graph/undirected-graph.test.ts b/test/unit/data-structures/graph/undirected-graph.test.ts index 4ce28cc..91cb49a 100644 --- a/test/unit/data-structures/graph/undirected-graph.test.ts +++ b/test/unit/data-structures/graph/undirected-graph.test.ts @@ -264,7 +264,7 @@ describe('cycles, strongly connected components, bridges, articular points in Un expect(lowMap.size).toBe(8); }); -it('Should return Infinity if dest is not found', () => { +it('Should return Number.MAX_SAFE_INTEGER if dest is not found', () => { const graph = new UndirectedGraph(); for (let i = 0; i < 3; ++i) { @@ -274,7 +274,7 @@ it('Should return Infinity if dest is not found', () => { graph.addEdge(0, 1, 1); const minCost02 = graph.getMinCostBetween(0, 2, true); - expect(minCost02).toBe(Infinity); + expect(minCost02).toBe(Number.MAX_SAFE_INTEGER); const minCost01 = graph.getMinCostBetween(0, 1, true); expect(minCost01).toBe(1); diff --git a/test/unit/data-structures/linked-list/singly-linked-list.test.ts b/test/unit/data-structures/linked-list/singly-linked-list.test.ts index af1bebf..00405ae 100644 --- a/test/unit/data-structures/linked-list/singly-linked-list.test.ts +++ b/test/unit/data-structures/linked-list/singly-linked-list.test.ts @@ -1,4 +1,4 @@ -import { SinglyLinkedList, SinglyLinkedListNode } from '../../../../src'; +import { SinglyLinkedList, SinglyLinkedListNode, Stack } from '../../../../src'; describe('SinglyLinkedListNode', () => { it('should SinglyLinkedList', () => { @@ -649,3 +649,93 @@ describe('iterable methods', () => { expect(sl.reduce((accumulator, element) => accumulator + element, 0)).toEqual(6); }); }); + +describe('classic uses', () => { + + it('@example implementation of a basic text editor', () => { + + class TextEditor { + private content: SinglyLinkedList; + private cursorIndex: number; + private undoStack: Stack<{ operation: string; data?: any }>; + + constructor() { + this.content = new SinglyLinkedList(); + this.cursorIndex = 0; // Cursor starts at the beginning + this.undoStack = new Stack<{ operation: string; data?: any }>(); // Stack to keep track of operations for undo + } + + /** + * Inserts a character at the current cursor position. + * @param char - The character to insert. + */ + insert(char: string) { + this.content.addAt(this.cursorIndex, char); + this.cursorIndex++; + this.undoStack.push({ operation: 'insert', data: { index: this.cursorIndex - 1 } }); + } + + /** + * Deletes the character at the current cursor position. + * If the cursor is at the end, deletes the character before the cursor. + */ + delete() { + if (this.cursorIndex === 0) return; // Nothing to delete + const deleted = this.content.deleteAt(this.cursorIndex - 1); + this.cursorIndex--; + this.undoStack.push({ operation: 'delete', data: { index: this.cursorIndex, char: deleted } }); + } + + /** + * Moves the cursor to a specific position. + * @param index - The position to move the cursor to. + */ + moveCursor(index: number) { + this.cursorIndex = Math.max(0, Math.min(index, this.content.length)); + } + + /** + * Undoes the last operation (insert or delete). + */ + undo() { + if (this.undoStack.size === 0) return; // No operations to undo + const lastAction = this.undoStack.pop(); + + if (lastAction!.operation === 'insert') { + this.content.deleteAt(lastAction!.data.index); + this.cursorIndex = lastAction!.data.index; + } else if (lastAction!.operation === 'delete') { + this.content.addAt(lastAction!.data.index, lastAction!.data.char); + this.cursorIndex = lastAction!.data.index + 1; + } + } + + /** + * Displays the current text content of the editor. + * @returns The concatenated string representation of the text. + */ + getText(): string { + return [...this.content].join(''); + } + } + + // Example Usage + const editor = new TextEditor(); + editor.insert('H'); + editor.insert('e'); + editor.insert('l'); + editor.insert('l'); + editor.insert('o'); + expect(editor.getText()).toBe('Hello'); // Output: "Hello" + + editor.delete(); + expect(editor.getText()).toBe('Hell'); // Output: "Hell" + + editor.undo(); + expect(editor.getText()).toBe('Hello'); // Output: "Hello" + + editor.moveCursor(1); + editor.insert('a'); + expect(editor.getText()).toBe('Haello'); // Output: "Haello" + }); +});