changes

.prettierrc

@@ -1,6 +1,6 @@
 {
   "singleQuote": true,
   "bracketSpacing": false,
-  "semi": false,
+  "semi": true,
   "printWidth": 80
 }

.travis.yml

@@ -1,6 +1,6 @@
 language:
 node_js:
-  - "8"
+  - '8'
 install:
   - npm install
   - npm install -g codecov

.vscode/launch.json

@@ -1,36 +1,33 @@
 {
-    // Use IntelliSense to learn about possible attributes.
-    // Hover to view descriptions of existing attributes.
-    // For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
-    "version": "0.2.0",
-    "configurations": [
-      {
-        "name": "Launch Program",
-        "program": "${relativeFile}",
-        "request": "launch",
-        "skipFiles": [
-          "<node_internals>/**"
-        ],
-        "type": "pwa-node"
-      },
-      {
-        "type": "node",
-        "request": "launch",
-        "name": "Jest All",
-        "program": "${workspaceFolder}/node_modules/jest/bin/jest",
-        "args": ["--runInBand"],
-        "console": "integratedTerminal",
-        "internalConsoleOptions": "neverOpen"
-      },
-      {
-        "type": "node",
-        "request": "launch",
-        "name": "Jest Current File",
-        "program": "${workspaceFolder}/node_modules/jest/bin/jest",
-        "args": ["${relativeFile}"],
-        "console": "integratedTerminal",
-        "internalConsoleOptions": "neverOpen"
-      }
-    ]
-  }
-
+  // Use IntelliSense to learn about possible attributes.
+  // Hover to view descriptions of existing attributes.
+  // For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
+  "version": "0.2.0",
+  "configurations": [
+    {
+      "name": "Launch Program",
+      "program": "${relativeFile}",
+      "request": "launch",
+      "skipFiles": ["<node_internals>/**"],
+      "type": "pwa-node"
+    },
+    {
+      "type": "node",
+      "request": "launch",
+      "name": "Jest All",
+      "program": "${workspaceFolder}/node_modules/jest/bin/jest",
+      "args": ["--runInBand"],
+      "console": "integratedTerminal",
+      "internalConsoleOptions": "neverOpen"
+    },
+    {
+      "type": "node",
+      "request": "launch",
+      "name": "Jest Current File",
+      "program": "${workspaceFolder}/node_modules/jest/bin/jest",
+      "args": ["${relativeFile}"],
+      "console": "integratedTerminal",
+      "internalConsoleOptions": "neverOpen"
+    }
+  ]
+}

Readme.md

@@ -15,33 +15,33 @@ Written in ES6 🔥, tested with Jest 🔍 and some ⏱ perf measurements
 
 ## Data Structures
 
-* [Array](src/dataStructures/Array)
-* [Hash Table](src/dataStructures/HashTable)
-* [Set](src/dataStructures/Set)
-* [Singly Linked List](src/dataStructures/SinglyLinkedList)
-* [Doubly Linked List](src/dataStructures/DoublyLinkedList)
-* [Stack](src/dataStructures/Stack)
-* [Queue](src/dataStructures/Queue)
-* Tree
-* [Binary search tree](src/dataStructures/BinarySearchTree)
-* Trie
-* Graph
+- [Array](src/dataStructures/Array)
+- [Hash Table](src/dataStructures/HashTable)
+- [Set](src/dataStructures/Set)
+- [Singly Linked List](src/dataStructures/SinglyLinkedList)
+- [Doubly Linked List](src/dataStructures/DoublyLinkedList)
+- [Stack](src/dataStructures/Stack)
+- [Queue](src/dataStructures/Queue)
+- Tree
+- [Binary search tree](src/dataStructures/BinarySearchTree)
+- Trie
+- Graph
 
 ## Algorithms
 
-* [Fizz-Buzz](src/algorithms/FizzBuzz)
-* [isPalindrome](src/algorithms/isPalindrome)
-* [caesarCipher](src/algorithms/caesarCipher)
-* [reverseWords](src/algorithms/reverseWords)
-* [reverseArrayInPlace](src/algorithms/reverseArrayInPlace)
-* [meanMedianMode](src/algorithms/meanMedianMode)
-* [twoSum](src/algorithms/twoSum)
-* [getEvenOccurrence](src/algorithms/getEvenOccurrence): Find the first even occurrence of a number in an array
-* [getAllPermutations](src/algorithms/getPermutations): Get all the permutations of a string
-* [Roman to Numerals](src/algorithms/romanToNumerals): Translate Romans into numerals
-* [QueueTwoStacks](src/algorithms/queueStacks): Implement a queue with 2 stacks.
-* [GetMaxStack](src/algorithms/getMaxStack): Get the largest item in a stack
-* [ResponseHandler](src/algorithms/responseHandler): Add handlers and implement fallbacks
+- [Fizz-Buzz](src/algorithms/FizzBuzz)
+- [isPalindrome](src/algorithms/isPalindrome)
+- [caesarCipher](src/algorithms/caesarCipher)
+- [reverseWords](src/algorithms/reverseWords)
+- [reverseArrayInPlace](src/algorithms/reverseArrayInPlace)
+- [meanMedianMode](src/algorithms/meanMedianMode)
+- [twoSum](src/algorithms/twoSum)
+- [getEvenOccurrence](src/algorithms/getEvenOccurrence): Find the first even occurrence of a number in an array
+- [getAllPermutations](src/algorithms/getPermutations): Get all the permutations of a string
+- [Roman to Numerals](src/algorithms/romanToNumerals): Translate Romans into numerals
+- [QueueTwoStacks](src/algorithms/queueStacks): Implement a queue with 2 stacks.
+- [GetMaxStack](src/algorithms/getMaxStack): Get the largest item in a stack
+- [ResponseHandler](src/algorithms/responseHandler): Add handlers and implement fallbacks
 
 [snyk-image]: https://snyk.io/test/github/albinotonnina/javascript-problems/badge.svg
 [snyk-url]: https://snyk.io/test/github/albinotonnina/javascript-problems

babel.config.js

@@ -1,5 +1,5 @@
 module.exports = {
-  "env": {
-    "test": { presets: [ "@babel/preset-env" ] }
-  }
-};
+  env: {
+    test: {presets: ['@babel/preset-env']},
+  },
+};

map.js

@@ -1 +1 @@
-module.exports = test => test.replace(/\.tap\.js$/, '.js')
+module.exports = (test) => test.replace(/\.tap\.js$/, '.js');

src/algorithms/FizzBuzz/README.md

@@ -1,9 +1,9 @@
 # ⚗️ Fizz-Buzz
 
-The "Fizz-Buzz test" is an interview question designed to help filter out the 99.5% of programming job candidates who can't seem to program their way out of a wet paper bag. 
+The "Fizz-Buzz test" is an interview question designed to help filter out the 99.5% of programming job candidates who can't seem to program their way out of a wet paper bag.
 
 The text of the programming assignment is as follows:
 
 > Write a program that prints the numbers from 1 to 100. But for multiples of three print “Fizz” instead of the number and for the multiples of five print “Buzz”. For numbers which are multiples of both three and five print “FizzBuzz”.
 
-[check the code](fizzbuzz.js) and the [test](__tests__/fizzbuzz.test.js)
+[check the code](fizzbuzz.js) and the [test](__tests__/fizzbuzz.test.js)

src/algorithms/FizzBuzz/__tests__/fizzbuzz.test.js

@@ -1,6 +1,6 @@
-import { displayPerfTime } from '../../../utils/perf-utils'
+import {displayPerfTime} from '../../../utils/perf-utils';
 
-import { fizzBuzz1, fizzBuzz2 } from '../fizzbuzz'
+import {fizzBuzz1, fizzBuzz2} from '../fizzbuzz';
 
 describe('Fizz-Buzz', () => {
   const vals = [
@@ -103,43 +103,43 @@ describe('Fizz-Buzz', () => {
     97,
     98,
     'Fizz',
-    'Buzz'
-  ]
+    'Buzz',
+  ];
 
   it('should pass with fizzBuzz1', () => {
-    expect(fizzBuzz1(100)).toEqual(vals)
-  })
+    expect(fizzBuzz1(100)).toEqual(vals);
+  });
 
   it('should pass with fizzBuzz2', () => {
-    expect(fizzBuzz2(100)).toEqual(vals)
-  })
+    expect(fizzBuzz2(100)).toEqual(vals);
+  });
 
   describe('Performance', () => {
     it('will display perftime, num=10', () => {
       displayPerfTime('fizzBuzz1(10)', () => {
-        fizzBuzz1(10)
-      })
+        fizzBuzz1(10);
+      });
       displayPerfTime('fizzBuzz2(10)', () => {
-        fizzBuzz2(10)
-      })
-    })
+        fizzBuzz2(10);
+      });
+    });
 
     it('will display perftime, num=100', () => {
       displayPerfTime('fizzBuzz1(100)', () => {
-        fizzBuzz1(10)
-      })
+        fizzBuzz1(10);
+      });
       displayPerfTime('fizzBuzz2(100)', () => {
-        fizzBuzz2(10)
-      })
-    })
+        fizzBuzz2(10);
+      });
+    });
 
     it('will display perftime, num=1000', () => {
       displayPerfTime('fizzBuzz1(1000)', () => {
-        fizzBuzz1(1000)
-      })
+        fizzBuzz1(1000);
+      });
       displayPerfTime('fizzBuzz2(1000)', () => {
-        fizzBuzz2(1000)
-      })
-    })
-  })
-})
+        fizzBuzz2(1000);
+      });
+    });
+  });
+});

src/algorithms/FizzBuzz/fizzbuzz.js

@@ -1,13 +1,16 @@
-export const fizzBuzz1 = num => {
+export const fizzBuzz1 = (num) => {
   return [...Array(num).keys()]
     .map((_, i) => i + 1)
-    .map(
-      i =>
-        i % 15 === 0
-          ? 'FizzBuzz'
-          : i % 3 === 0 ? 'Fizz' : i % 5 === 0 ? 'Buzz' : i
-    )
-}
+    .map((i) =>
+      i % 15 === 0
+        ? 'FizzBuzz'
+        : i % 3 === 0
+        ? 'Fizz'
+        : i % 5 === 0
+        ? 'Buzz'
+        : i
+    );
+};
 
 /*
 
@@ -24,20 +27,20 @@ now we apply FizzBuzz logic, by testing all the possible combinations in the cor
 
 */
 
-export const fizzBuzz2 = num => {
-  let fizzedBuzzedArr = []
+export const fizzBuzz2 = (num) => {
+  let fizzedBuzzedArr = [];
 
   for (let i = 1; i <= num; i++) {
     if (i % 3 === 0 && i % 5 === 0) {
-      fizzedBuzzedArr.push('FizzBuzz')
+      fizzedBuzzedArr.push('FizzBuzz');
     } else if (i % 3 === 0) {
-      fizzedBuzzedArr.push('Fizz')
+      fizzedBuzzedArr.push('Fizz');
     } else if (i % 5 === 0) {
-      fizzedBuzzedArr.push('Buzz')
+      fizzedBuzzedArr.push('Buzz');
     } else {
-      fizzedBuzzedArr.push(i)
+      fizzedBuzzedArr.push(i);
     }
   }
 
-  return fizzedBuzzedArr
-}
+  return fizzedBuzzedArr;
+};

src/algorithms/RiverSizes/index.js

@@ -0,0 +1,43 @@
+function riverSizes(matrix) {
+  const sizes = [];
+  const visited = matrix.map((row) => row.map(() => false));
+  for (let i = 0; i < matrix.length; i++) {
+    for (let j = 0; j < matrix[i].length; j++) {
+      if (visited[i][j]) continue;
+      traverseNode(i, j, matrix, visited, sizes);
+    }
+  }
+  return sizes;
+}
+
+function traverseNode(i, j, matrix, visited, sizes) {
+  let currentRiverSize = 0;
+  const nodesToExplore = [[i, j]];
+  while (nodesToExplore.length) {
+    const currentNode = nodesToExplore.pop();
+    i = currentNode[0];
+    j = currentNode[1];
+    if (visited[i][j]) continue;
+    visited[i][j] = true;
+    if (matrix[i][j] === 0) continue;
+    currentRiverSize++;
+    const unvisitedNeighbors = getUnvisitedNeighbors(i, j, matrix, visited);
+    for (const neighbor of unvisitedNeighbors) {
+      nodesToExplore.push(neighbor);
+    }
+  }
+  if (currentRiverSize > 0) sizes.push(currentRiverSize);
+}
+
+function getUnvisitedNeighbors(i, j, matrix, visited) {
+  const unvisitedNeighbors = [];
+  if (i > 0 && !visited[i - 1][j]) unvisitedNeighbors.push([i - 1, j]);
+  if (i < matrix.length - 1 && !visited[i + 1][j])
+    unvisitedNeighbors.push([i + 1, j]);
+  if (j > 0 && !visited[i][j - 1]) unvisitedNeighbors.push([i, j - 1]);
+  if (j < matrix[0].length - 1 && !visited[i][j + 1])
+    unvisitedNeighbors.push([i, j + 1]);
+  return unvisitedNeighbors;
+}
+
+export default riverSizes;