✨ Add episode 25

Author: w3cj

.eslintrc.js

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+module.exports = {
+    'env': {
+        'commonjs': true,
+        'es6': true,
+        'node': true
+    },
+    'extends': 'eslint:recommended',
+    'globals': {
+        'Atomics': 'readonly',
+        'SharedArrayBuffer': 'readonly'
+    },
+    'parserOptions': {
+        'ecmaVersion': 2018
+    },
+    'rules': {
+        'indent': [
+            'error',
+            2
+        ],
+        'linebreak-style': [
+            'error',
+            'unix'
+        ],
+        'quotes': [
+            'error',
+            'single'
+        ],
+        'semi': [
+            'error',
+            'always'
+        ],
+        'no-console': 0
+    }
+};

episode_025/README.md

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+# Episode 25
+
+## 7 kyu
+
+* https://www.codewars.com/kata/reverse-words/train/javascript
+
+## 6 kyu
+
+* https://www.codewars.com/kata/detect-pangram/train/javascript
+
+## 5 kyu
+
+* https://www.codewars.com/kata/hello-w-dot-dot-dot-wait-what/train/javascript

episode_025/detect-pangram.js

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+function isPangram(string) {
+  // create an object with every lower case letter as a property
+  const allLetters = {};
+  for (let i = 97; i <= 122; i++) {
+    allLetters[String.fromCharCode(i)] = true;
+  }
+
+  // iterate over the string
+  for (let i = 0; i < string.length; i++) {
+    const character = string[i].toLowerCase();
+    // delete / remove the lowercase letter from the above object
+    delete allLetters[character];
+  }
+
+  // if object has no properties return true
+  return Object.keys(allLetters).length === 0;
+}
+
+function isPangram(string) {
+  // create a Set from only letters a-z in the string  
+  const allLetters = new Set(string.toLowerCase().match(/[a-z]/g));
+  // if length of Set is 26 return true!
+  return allLetters.size === 26;
+}
+
+// Daniel!
+​function isPangram(string) {
+  let newstr = string.toLowerCase().match(/[a-z]/g, "")
+  let set1 = new Set(newstr);
+  return set1.size === 26;
+}
+
+
+const input1 = 'The quick brown fox jumps over the lazy dog.';
+console.log(isPangram(input1), true);
+const input2 = 'This is not a pangram.';
+console.log(isPangram(input2), false);

episode_025/hello-w-dot-dot-dot-wait-what.js

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+function waitWhat() {
+  const [ ,H ] = [].shift.name.toUpperCase();
+  const [ e ] = [].every.name;
+  const [ l ] = [].lastIndexOf.name;
+  const [ o ] = Array.of.name;
+
+  const [ , a ] = false.toString();
+  const zero = [].length;
+  const space = a.charCodeAt(zero) - a.toUpperCase().charCodeAt(zero);
+
+  const [ ,,,,W ] = [].copyWithin.name;
+  const [ r ] = [].reverse.name;
+  const [ ,,,d ] = [].find.name;
+
+  const exclame = space + [true].length;
+
+  return H + e + l + l + o
+    + String.fromCharCode(space)
+    + W + o + r + l + d
+    + String.fromCharCode(exclame);
+}
+
+console.log(waitWhat());
+

episode_025/reverse-words.js

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+function reverseWords(str) {
+  // a place to store the reversed words
+  let reversedStr = '';
+  // a place to store an individually reversed word
+  let reversedWord = '';
+  // iterate over the string from index 0 to the end
+  for (let i = 0; i < str.length; i++) {
+    const character = str[i];    
+    // if the current character is not a space
+    if (character !== ' ') {
+      // prepend letter to individually reversed word
+      reversedWord = character + reversedWord;
+    } else {
+      // append individually reversed word to the whole reversed words
+      reversedStr += reversedWord + ' ';
+      reversedWord = '';
+      // append the space character
+    }
+  }
+  // return the reversed words
+  return reversedStr + reversedWord;
+}
+
+function reverseWords(str) {
+  let reversedStr = '';
+  let reversedWord = '';
+  for (let i = 0; i < str.length; i++) {
+    const character = str[i];    
+    if (character !== ' ') {
+      reversedWord = character + reversedWord;
+    } else {
+      reversedStr += reversedWord + ' ';
+      reversedWord = '';
+    }
+  }
+  return reversedStr + reversedWord;
+}
+
+function reverseWord(word) {
+  return word.split('').reverse().join('');
+}
+
+function reverseWord(word) {
+  return [...word].reverse().join('');
+}
+
+function reverseWords(str) {
+  return str.split(' ').map(reverseWord).join(' ');
+}
+
+function reverseWords(str) {
+  return str.split(' ').map(word => [...word].reverse().join('')).join(' ');
+}
+
+function reverseWords(str) {
+  let reversedStr = '';
+  let reversedWord = '';
+  Array.prototype.forEach.call(str, (character) => {
+    if (character !== ' ') {
+      reversedWord = character + reversedWord;
+    } else {
+      reversedStr += reversedWord + ' ';
+      reversedWord = '';
+    }
+  });
+  return reversedStr + reversedWord;
+}
+
+function reverseWords(str) {
+  let reversedWord = '';
+  return Array.prototype.reduce.call(str, (reversedStr, character) => {
+    if (character !== ' ') {
+      reversedWord = character + reversedWord;
+    } else {
+      reversedStr += reversedWord + ' ';
+      reversedWord = '';
+    }
+    return reversedStr;
+  }, '') + reversedWord;
+}
+
+function reverseWords(str, reversedWord = '') {
+  return Array.prototype.reduce.call(str, (reversedStr, character) => (character !== ' ' ? reversedWord = character + reversedWord : (reversedStr += reversedWord + ' ', reversedWord = ''), reversedStr), '') + reversedWord;
+}
+
+function reverseWords(str, reversedWord = '') {
+  return [].reduce.call(str, (reversedStr, character) => (character !== ' ' ? reversedWord = character + reversedWord : (reversedStr += reversedWord + ' ', reversedWord = ''), reversedStr), '') + reversedWord;
+}
+
+// ALCA!!!
+const reverseWord = s => s.split('').reduce((p, n) => (n === ' ' ? (p[0] += p[1] + n, p[1] = '') : p[1] = n + p[1], p), [ '', '' ]).join('');
+
+console.log(reverseWords('The quick brown fox jumps over the lazy dog.') == 'ehT kciuq nworb xof spmuj revo eht yzal .god');
+console.log(reverseWords('apple') == 'elppa');
+console.log(reverseWords('a b c d') == 'a b c d');
+console.log(reverseWords('double  spaced  words') == 'elbuod  decaps  sdrow');