Merge branch 'dev' of github.com:danielyxie/bitburner into improvement/stats-augs-ui

doc/source/basicgameplay/codingcontracts.rst

@@ -196,6 +196,23 @@ The list contains the name of (i.e. the value returned by
 |                                    | |                                                                                        |
 |                                    | | Determine how many unique paths there are from start to finish.                        |
 +------------------------------------+------------------------------------------------------------------------------------------+
+| Shortest Path in a Grid            | | You are given a 2D array of numbers (array of array of numbers) representing           |
+|                                    | | a grid. The 2D array contains 1's and 0's, where 1 represents an obstacle and          |
+|                                    | | 0 represents a free space.                                                             |
+|                                    | |                                                                                        |
+|                                    | | Assume you are initially positioned in top-left corner of that grid and that you       |
+|                                    | | are trying to reach the bottom-right corner. In each step, you may move to the up,     |
+|                                    | | down, left or right. Furthermore, you cannot move onto spaces which have obstacles.    |
+|                                    | |                                                                                        |
+|                                    | | Determine if paths exist from start to destination, and find the shortest one.         |
+|                                    | |                                                                                        |
+|                                    | | Examples:                                                                              |
+|                                    | |  [[0,1,0,0,0],                                                                         |
+|                                    | |   [0,0,0,1,0]] -> "DRRURRD"                                                            |
+|                                    | |  [[0,1],                                                                               |
+|                                    | |   [1,0]]       -> ""                                                                   |
+|                                    | |                                                                                        |
++------------------------------------+------------------------------------------------------------------------------------------+
 | Sanitize Parentheses in Expression | | Given a string with parentheses and letters, remove the minimum number of invalid      |
 |                                    | | parentheses in order to validate the string. If there are multiple minimal ways        |
 |                                    | | to validate the string, provide all of the possible results.                           |

src/Augmentation/Augmentation.tsx

@@ -2,7 +2,6 @@
 import * as React from "react";
 import { IMap } from "../types";
 
-import { BitNodeMultipliers } from "../BitNode/BitNodeMultipliers";
 import { Faction } from "../Faction/Faction";
 import { Factions } from "../Faction/Factions";
 import { numeralWrapper } from "../ui/numeralFormat";

src/Augmentation/AugmentationHelpers.tsx

@@ -154,8 +154,8 @@ function applyAugmentation(aug: IPlayerOwnedAugmentation, reapply = false): void
   }
 }
 
-function installAugmentations(): boolean {
+function installAugmentations(force?: boolean): boolean {
-  if (Player.queuedAugmentations.length == 0) {
+  if (Player.queuedAugmentations.length == 0 && !force) {
     dialogBoxCreate("You have not purchased any Augmentations to install!");
     return false;
   }
@@ -185,12 +185,14 @@ function installAugmentations(): boolean {
     augmentationList += aug.name + level + "<br>";
   }
   Player.queuedAugmentations = [];
+  if (!force) {
     dialogBoxCreate(
       "You slowly drift to sleep as scientists put you under in order " +
         "to install the following Augmentations:<br>" +
         augmentationList +
         "<br>You wake up in your home...you feel different...",
     );
+  }
   prestigeAugmentation();
   return true;
 }

src/Faction/FactionHelpers.tsx

@@ -203,7 +203,7 @@ export const getFactionAugmentationsFiltered = (player: IPlayer, faction: Factio
     // Remove special augs
     augs = augs.filter((a) => !a.isSpecial);
 
-    const blacklist: string[] = [AugmentationNames.NeuroFluxGovernor];
+    const blacklist: string[] = [AugmentationNames.NeuroFluxGovernor, AugmentationNames.CongruityImplant];
 
     if (player.bitNodeN !== 2) {
       // TRP is not available outside of BN2 for Gangs

src/Gang/Gang.ts

@@ -225,7 +225,6 @@ export class Gang implements IGang {
           if (AllGangs[otherGang].territory <= 0) return;
           const territoryGain = calculateTerritoryGain(thisGang, otherGang);
           AllGangs[thisGang].territory += territoryGain;
-          if (AllGangs[thisGang].territory > 0.999) AllGangs[thisGang].territory = 1;
           AllGangs[otherGang].territory -= territoryGain;
           if (thisGang === gangName) {
             this.clash(true); // Player won
@@ -239,9 +238,7 @@ export class Gang implements IGang {
           if (AllGangs[thisGang].territory <= 0) return;
           const territoryGain = calculateTerritoryGain(otherGang, thisGang);
           AllGangs[thisGang].territory -= territoryGain;
-          if (AllGangs[otherGang].territory < 0.001) AllGangs[otherGang].territory = 0;
           AllGangs[otherGang].territory += territoryGain;
-          if (AllGangs[otherGang].territory > 0.999) AllGangs[otherGang].territory = 1;
           if (thisGang === gangName) {
             this.clash(false); // Player lost
           } else if (otherGang === gangName) {
@@ -251,6 +248,11 @@ export class Gang implements IGang {
             AllGangs[thisGang].power *= 1 / 1.01;
           }
         }
+
+        const total = Object.values(AllGangs)
+          .map((g) => g.territory)
+          .reduce((p, c) => p + c, 0);
+        Object.values(AllGangs).forEach((g) => (g.territory /= total));
       }
     }
   }

src/NetscriptFunctions/Singularity.ts

@@ -6,7 +6,6 @@ import { startWorkerScript } from "../NetscriptWorker";
 import { Augmentation } from "../Augmentation/Augmentation";
 import { Augmentations } from "../Augmentation/Augmentations";
 import { augmentationExists, installAugmentations } from "../Augmentation/AugmentationHelpers";
-import { prestigeAugmentation } from "../Prestige";
 import { AugmentationNames } from "../Augmentation/data/AugmentationNames";
 import { killWorkerScript } from "../Netscript/killWorkerScript";
 import { CONSTANTS } from "../Constants";
@@ -212,7 +211,7 @@ export function NetscriptSingularity(
 
       workerScript.log("softReset", () => "Soft resetting. This will cause this script to be killed");
       setTimeout(() => {
-        prestigeAugmentation();
+        installAugmentations(true);
         runAfterReset(cbScript);
       }, 0);
 

src/data/codingcontracttypes.ts

@@ -1,5 +1,7 @@
 import { getRandomInt } from "../utils/helpers/getRandomInt";
+import { MinHeap } from "../utils/Heap";
 
+import { HammingEncode, HammingDecode } from "../utils/HammingCodeTools";
 /* tslint:disable:completed-docs no-magic-numbers arrow-return-shorthand */
 
 /* Function that generates a valid 'data' for a contract type */
@@ -794,6 +796,140 @@ export const codingContractTypesMetadata: ICodingContractTypeMetadata[] = [
       return obstacleGrid[obstacleGrid.length - 1][obstacleGrid[0].length - 1] === parseInt(ans);
     },
   },
+  {
+    name: "Shortest Path in a Grid",
+    desc: (data: number[][]): string => {
+      return [
+        "You are located in the top-left corner of the following grid:\n\n",
+        `  [${data.map((line) => "[" + line + "]").join(",\n   ")}]\n\n`,
+        "You are trying to find the shortest path to the bottom-right corner of the grid,",
+        "but there are obstacles on the grid that you cannot move onto.",
+        "These obstacles are denoted by '1', while empty spaces are denoted by 0.\n\n",
+        "Determine the shortest path from start to finish, if one exists.",
+        "The answer should be given as a string of UDLR characters, indicating the moves along the path\n\n",
+        "NOTE: If there are multiple equally short paths, any of them is accepted as answer.",
+        "If there is no path, the answer should be an empty string.\n",
+        "NOTE: The data returned for this contract is an 2D array of numbers representing the grid.\n\n",
+        "Examples:\n\n",
+        "    [[0,1,0,0,0],\n",
+        "     [0,0,0,1,0]]\n",
+        "\n",
+        "Answer: 'DRRURRD'\n\n",
+        "    [[0,1],\n",
+        "     [1,0]]\n",
+        "\n",
+        "Answer: ''\n\n",
+      ].join(" ");
+    },
+    difficulty: 7,
+    numTries: 10,
+    gen: (): number[][] => {
+      const height = getRandomInt(6, 12);
+      const width = getRandomInt(6, 12);
+      const dstY = height - 1;
+      const dstX = width - 1;
+      const minPathLength = dstY + dstX; // Math.abs(dstY - srcY) + Math.abs(dstX - srcX)
+
+      const grid: number[][] = new Array(height);
+      for (let y = 0; y < height; y++) grid[y] = new Array(width).fill(0);
+
+      for (let y = 0; y < height; y++) {
+        for (let x = 0; x < width; x++) {
+          if (y == 0 && x == 0) continue; // Don't block start
+          if (y == dstY && x == dstX) continue; // Don't block destination
+
+          // Generate more obstacles the farther a position is from start and destination.
+          // Raw distance factor peaks at 50% at half-way mark. Rescale to 40% max.
+          // Obstacle chance range of [15%, 40%] produces ~78% solvable puzzles
+          const distanceFactor = (Math.min(y + x, dstY - y + dstX - x) / minPathLength) * 0.8;
+          if (Math.random() < Math.max(0.15, distanceFactor)) grid[y][x] = 1;
+        }
+      }
+
+      return grid;
+    },
+    solver: (data: number[][], ans: string): boolean => {
+      const width = data[0].length;
+      const height = data.length;
+      const dstY = height - 1;
+      const dstX = width - 1;
+
+      const distance: [number][] = new Array(height);
+      //const prev: [[number, number] | undefined][] = new Array(height);
+      const queue = new MinHeap<[number, number]>();
+
+      for (let y = 0; y < height; y++) {
+        distance[y] = new Array(width).fill(Infinity) as [number];
+        //prev[y] = new Array(width).fill(undefined) as [undefined];
+      }
+
+      function validPosition(y: number, x: number): boolean {
+        return y >= 0 && y < height && x >= 0 && x < width && data[y][x] == 0;
+      }
+
+      // List in-bounds and passable neighbors
+      function* neighbors(y: number, x: number): Generator<[number, number]> {
+        if (validPosition(y - 1, x)) yield [y - 1, x]; // Up
+        if (validPosition(y + 1, x)) yield [y + 1, x]; // Down
+        if (validPosition(y, x - 1)) yield [y, x - 1]; // Left
+        if (validPosition(y, x + 1)) yield [y, x + 1]; // Right
+      }
+
+      // Prepare starting point
+      distance[0][0] = 0;
+      queue.push([0, 0], 0);
+
+      // Take next-nearest position and expand potential paths from there
+      while (queue.size > 0) {
+        const [y, x] = queue.pop() as [number, number];
+        for (const [yN, xN] of neighbors(y, x)) {
+          const d = distance[y][x] + 1;
+          if (d < distance[yN][xN]) {
+            if (distance[yN][xN] == Infinity)
+              // Not reached previously
+              queue.push([yN, xN], d);
+            // Found a shorter path
+            else queue.changeWeight(([yQ, xQ]) => yQ == yN && xQ == xN, d);
+            //prev[yN][xN] = [y, x];
+            distance[yN][xN] = d;
+          }
+        }
+      }
+
+      // No path at all?
+      if (distance[dstY][dstX] == Infinity) return ans == "";
+
+      // There is a solution, require that the answer path is as short as the shortest
+      // path we found
+      if (ans.length > distance[dstY][dstX]) return false;
+
+      // Further verify that the answer path is a valid path
+      let ansX = 0;
+      let ansY = 0;
+      for (const direction of ans) {
+        switch (direction) {
+          case "U":
+            ansY -= 1;
+            break;
+          case "D":
+            ansY += 1;
+            break;
+          case "L":
+            ansX -= 1;
+            break;
+          case "R":
+            ansX += 1;
+            break;
+          default:
+            return false; // Invalid character
+        }
+        if (!validPosition(ansY, ansX)) return false;
+      }
+
+      // Path was valid, finally verify that the answer path brought us to the end coordinates
+      return ansY == dstY && ansX == dstX;
+    },
+  },
   {
     desc: (data: string): string => {
       return [
@@ -1008,4 +1144,62 @@ export const codingContractTypesMetadata: ICodingContractTypeMetadata[] = [
       return true;
     },
   },
+  {
+    name: "HammingCodes: Integer to encoded Binary",
+    numTries: 10,
+    difficulty: 5,
+    desc: (n: number): string => {
+      return [
+        "You are given the following decimal Value: \n",
+        `${n} \n`,
+        "Convert it into a binary string and encode it as a 'Hamming-Code'. eg:\n ",
+        "Value 8 will result into binary '1000', which will be encoded",
+        "with the pattern 'pppdpddd', where p is a paritybit and d a databit,\n",
+        "or '10101' (Value 21) will result into (pppdpdddpd) '1111101011'.\n\n",
+        "NOTE: You need an parity Bit on Index 0 as an 'overall'-paritybit. \n",
+        "NOTE 2: You should watch the HammingCode-video from 3Blue1Brown, which explains the 'rule' of encoding,",
+        "including the first Index parity-bit mentioned on the first note.\n\n",
+        "Now the only one rule for this encoding:\n",
+        " It's not allowed to add additional leading '0's to the binary value\n",
+        "That means, the binary value has to be encoded as it is",
+      ].join(" ");
+    },
+    gen: (): number => {
+      return getRandomInt(Math.pow(2, 4), Math.pow(2, getRandomInt(1, 57)));
+    },
+    solver: (data: number, ans: string): boolean => {
+      return ans === HammingEncode(data);
+    },
+  },
+  {
+    name: "HammingCodes: Encoded Binary to Integer",
+    difficulty: 8,
+    numTries: 10,
+    desc: (n: string): string => {
+      return [
+        "You are given the following encoded binary String: \n",
+        `'${n}' \n`,
+        "Treat it as a Hammingcode with 1 'possible' error on an random Index.\n",
+        "Find the 'possible' wrong bit, fix it and extract the decimal value, which is hidden inside the string.\n\n",
+        "Note: The length of the binary string is dynamic, but it's encoding/decoding is following Hammings 'rule'\n",
+        "Note 2: Index 0 is an 'overall' parity bit. Watch the Hammingcode-video from 3Blue1Brown for more information\n",
+        "Note 3: There's a ~55% chance for an altered Bit. So... MAYBE there is an altered Bit 😉\n",
+        "Extranote for automation: return the decimal value as a string",
+      ].join(" ");
+    },
+    gen: (): string => {
+      const _alteredBit = Math.round(Math.random());
+      const _buildArray: Array<string> = HammingEncode(
+        getRandomInt(Math.pow(2, 4), Math.pow(2, getRandomInt(1, 57))),
+      ).split("");
+      if (_alteredBit) {
+        const _randomIndex: number = getRandomInt(0, _buildArray.length - 1);
+        _buildArray[_randomIndex] = _buildArray[_randomIndex] == "0" ? "1" : "0";
+      }
+      return _buildArray.join("");
+    },
+    solver: (data: string, ans: string): boolean => {
+      return parseInt(ans, 10) === HammingDecode(data);
+    },
+  },
 ];

src/ui/GameRoot.tsx

@@ -310,7 +310,7 @@ export function GameRoot({ player, engine, terminal }: IProps): React.ReactEleme
 
   function softReset(): void {
     dialogBoxCreate("Soft Reset!");
-    prestigeAugmentation();
+    installAugmentations(true);
     resetErrorBoundary();
     Router.toTerminal();
   }

src/utils/HammingCodeTools.ts

@@ -0,0 +1,97 @@
+// by Discord: H3draut3r#6722, feel free to ask me any questions. i probably don't know the answer 🤣
+export function HammingEncode(value: number): string {
+  // encoding following Hammings rule
+  function HammingSumOfParity(_lengthOfDBits: number): number {
+    // will calculate the needed amount of parityBits 'without' the "overall"-Parity (that math took me 4 Days to get it working)
+    return _lengthOfDBits < 3 || _lengthOfDBits == 0 // oh and of course using ternary operators, it's a pretty neat function
+      ? _lengthOfDBits == 0
+        ? 0
+        : _lengthOfDBits + 1
+      : // the following math will only work, if the length is greater equal 3, otherwise it's "kind of" broken :D
+      Math.ceil(Math.log2(_lengthOfDBits * 2)) <=
+        Math.ceil(Math.log2(1 + _lengthOfDBits + Math.ceil(Math.log2(_lengthOfDBits))))
+      ? Math.ceil(Math.log2(_lengthOfDBits) + 1)
+      : Math.ceil(Math.log2(_lengthOfDBits));
+  }
+  const _data = value.toString(2).split(""); // first, change into binary string, then create array with 1 bit per index
+  const _sumParity: number = HammingSumOfParity(_data.length); // get the sum of needed parity bits (for later use in encoding)
+  const count = (arr: Array<string>, val: string): number =>
+    arr.reduce((a: number, v: string) => (v === val ? a + 1 : a), 0);
+  // function count for specific entries in the array, for later use
+
+  const _build = ["x", "x", ..._data.splice(0, 1)]; // init the "pre-build"
+  for (let i = 2; i < _sumParity; i++) {
+    // add new paritybits and the corresponding data bits (pre-building array)
+    _build.push("x", ..._data.splice(0, Math.pow(2, i) - 1));
+  }
+  // now the "calculation"... get the paritybits ('x') working
+  for (const index of _build.reduce(function (a: Array<number>, e: string, i: number) {
+    if (e == "x") a.push(i);
+    return a;
+  }, [])) {
+    // that reduce will result in an array of index numbers where the "x" is placed
+    const _tempcount = index + 1; // set the "stepsize" for the parityBit
+    const _temparray = []; // temporary array to store the extracted bits
+    const _tempdata = [..._build]; // only work with a copy of the _build
+    while (_tempdata[index] !== undefined) {
+      // as long as there are bits on the starting index, do "cut"
+      const _temp: Array<string> = _tempdata.splice(index, _tempcount * 2); // cut stepsize*2 bits, then...
+      _temparray.push(..._temp.splice(0, _tempcount)); // ... cut the result again and keep the first half
+    }
+    _temparray.splice(0, 1); // remove first bit, which is the parity one
+    _build[index] = (count(_temparray, "1") % 2).toString(); // count with remainder of 2 and"toString" to store the parityBit
+  } // parity done, now the "overall"-parity is set
+  _build.unshift((count(_build, "1") % 2).toString()); // has to be done as last element
+  return _build.join(""); // return the _build as string
+}
+
+export function HammingDecode(_data: string): number {
+  //check for altered bit and decode
+  const _build = _data.split(""); // ye, an array for working, again
+  const _testArray = []; //for the "truthtable". if any is false, the data has an altered bit, will check for and fix it
+  const _sumParity = Math.ceil(Math.log2(_data.length)); // sum of parity for later use
+  const count = (arr: Array<string>, val: string): number =>
+    arr.reduce((a: number, v: string) => (v === val ? a + 1 : a), 0);
+  // the count.... again ;)
+
+  let _overallParity = _build.splice(0, 1).join(""); // store first index, for checking in next step and fix the _build properly later on
+  _testArray.push(_overallParity == (count(_build, "1") % 2).toString() ? true : false); // first check with the overall parity bit
+  for (let i = 0; i < _sumParity; i++) {
+    // for the rest of the remaining parity bits we also "check"
+    const _tempIndex = Math.pow(2, i) - 1; // get the parityBits Index
+    const _tempStep = _tempIndex + 1; // set the stepsize
+    const _tempData = [..._build]; // get a "copy" of the build-data for working
+    const _tempArray = []; // init empty array for "testing"
+    while (_tempData[_tempIndex] != undefined) {
+      // extract from the copied data until the "starting" index is undefined
+      const _temp = [..._tempData.splice(_tempIndex, _tempStep * 2)]; // extract 2*stepsize
+      _tempArray.push(..._temp.splice(0, _tempStep)); // and cut again for keeping first half
+    }
+    const _tempParity = _tempArray.shift(); // and again save the first index separated for checking with the rest of the data
+    _testArray.push(_tempParity == (count(_tempArray, "1") % 2).toString() ? true : false);
+    // is the _tempParity the calculated data? push answer into the 'truthtable'
+  }
+  let _fixIndex = 0; // init the "fixing" index and start with 0
+  for (let i = 1; i < _sumParity + 1; i++) {
+    // simple binary adding for every boolean in the _testArray, starting from 2nd index of it
+    _fixIndex += _testArray[i] ? 0 : Math.pow(2, i) / 2;
+  }
+  _build.unshift(_overallParity); // now we need the "overall" parity back in it's place
+  // try fix the actual encoded binary string if there is an error
+  if (_fixIndex > 0 && _testArray[0] == false) {
+    // if the overall is false and the sum of calculated values is greater equal 0, fix the corresponding hamming-bit
+    _build[_fixIndex] = _build[_fixIndex] == "0" ? "1" : "0";
+  } else if (_testArray[0] == false) {
+    // otherwise, if the the overall_parity is the only wrong, fix that one
+    _overallParity = _overallParity == "0" ? "1" : "0";
+  } else if (_testArray[0] == true && _testArray.some((truth) => truth == false)) {
+    return 0; // uhm, there's some strange going on... 2 bits are altered? How? This should not happen 👀
+  }
+  // oof.. halfway through... we fixed an possible altered bit, now "extract" the parity-bits from the _build
+  for (let i = _sumParity; i >= 0; i--) {
+    // start from the last parity down the 2nd index one
+    _build.splice(Math.pow(2, i), 1);
+  }
+  _build.splice(0, 1); // remove the overall parity bit and we have our binary value
+  return parseInt(_build.join(""), 2); // parse the integer with redux 2 and we're done!
+}

src/utils/Heap.ts

@@ -0,0 +1,133 @@
+/** Binary heap. */
+abstract class BinHeap<T> {
+  /**
+   * Heap data array consisting of [weight, payload] pairs, arranged by weight
+   * to satisfy heap condition.
+   *
+   * Encodes the binary tree by storing tree root at index 0 and
+   * left child of element i at `i * 2 + 1` and
+   * right child of element i at `i * 2 + 2`.
+   */
+  protected data: [number, T][];
+
+  constructor() {
+    this.data = [];
+  }
+
+  /** Get number of elements in the heap. */
+  public get size(): number {
+    return this.data.length;
+  }
+
+  /** Add a new element to the heap. */
+  public push(value: T, weight: number): void {
+    const i = this.data.length;
+    this.data[i] = [weight, value];
+    this.heapifyUp(i);
+  }
+
+  /** Get the value of the root-most element of the heap, without changing the heap. */
+  public peek(): T | undefined {
+    if (this.data.length == 0) return undefined;
+
+    return this.data[0][1];
+  }
+
+  /** Remove the root-most element of the heap and return the removed element's value. */
+  public pop(): T | undefined {
+    if (this.data.length == 0) return undefined;
+
+    const value = this.data[0][1];
+
+    this.data[0] = this.data[this.data.length - 1];
+    this.data.length = this.data.length - 1;
+
+    this.heapifyDown(0);
+
+    return value;
+  }
+
+  /** Change the weight of an element in the heap. */
+  public changeWeight(predicate: (value: T) => boolean, weight: number): void {
+    // Find first element with matching value, if any
+    const i = this.data.findIndex((e) => predicate(e[1]));
+    if (i == -1) return;
+
+    // Update that element's weight
+    this.data[i][0] = weight;
+
+    // And re-heapify if needed
+    const p = Math.floor((i - 1) / 2);
+
+    if (!this.heapOrderABeforeB(this.data[p][0], this.data[i][0]))
+      // Needs to shift root-wards?
+      this.heapifyUp(i);
+    // Try shifting deeper
+    else this.heapifyDown(i);
+  }
+
+  /** Restore heap condition, starting at index i and traveling towards root. */
+  protected heapifyUp(i: number): void {
+    // Swap the new element up towards root until it reaches root position or
+    // settles under under a suitable parent
+    while (i > 0) {
+      const p = Math.floor((i - 1) / 2);
+
+      // Reached heap-ordered state already?
+      if (this.heapOrderABeforeB(this.data[p][0], this.data[i][0])) break;
+
+      // Swap
+      const tmp = this.data[p];
+      this.data[p] = this.data[i];
+      this.data[i] = tmp;
+
+      // And repeat at parent index
+      i = p;
+    }
+  }
+
+  /** Restore heap condition, starting at index i and traveling away from root. */
+  protected heapifyDown(i: number): void {
+    // Swap the shifted element down in the heap until it either reaches the
+    // bottom layer or is in correct order relative to it's children
+    while (i < this.data.length) {
+      const l = i * 2 + 1;
+      const r = i * 2 + 2;
+      let toSwap = i;
+
+      // Find which one of element i and it's children should be closest to root
+      if (l < this.data.length && this.heapOrderABeforeB(this.data[l][0], this.data[toSwap][0])) toSwap = l;
+      if (r < this.data.length && this.heapOrderABeforeB(this.data[r][0], this.data[toSwap][0])) toSwap = r;
+
+      // Already in order?
+      if (i == toSwap) break;
+
+      // Not in order. Swap child that should be closest to root up to 'i' and repeat
+      const tmp = this.data[toSwap];
+      this.data[toSwap] = this.data[i];
+      this.data[i] = tmp;
+
+      i = toSwap;
+    }
+  }
+
+  /**
+   * Should element with weight `weightA` be closer to root than element with
+   * weight `weightB`?
+   */
+  protected abstract heapOrderABeforeB(weightA: number, weightB: number): boolean;
+}
+
+/** Binary max-heap. */
+export class MaxHeap<T> extends BinHeap<T> {
+  heapOrderABeforeB(weightA: number, weightB: number): boolean {
+    return weightA > weightB;
+  }
+}
+
+/** Binary min-heap. */
+export class MinHeap<T> extends BinHeap<T> {
+  heapOrderABeforeB(weightA: number, weightB: number): boolean {
+    return weightA < weightB;
+  }
+}