rot13

Author: nerdrun

next_bigger_number_with_the_same_digits/main.js

@@ -1,13 +1,11 @@
 function nextBigger(n) {
-  const arrayWithNumbers = String(n).split('');
-  let index = arrayWithNumbers.length - 1;
-
-  index = arrayWithNumbers.findLastIndex((_, index) => arrayWithNumbers[index] > arrayWithNumbers[index - 1])
+  const arrayWithNumbers = [...String(n)];
+  let index = arrayWithNumbers.findLastIndex((_, index) => arrayWithNumbers[index] > arrayWithNumbers[index - 1])
   if (index <= 0) return -1;
 
   const [suffle, temp] = [arrayWithNumbers.splice(index).sort(), arrayWithNumbers[arrayWithNumbers.length - 1]];
 
-  index = suffle.findIndex(s => s > temp);
+  index = suffle.findIndex(value => value > temp);
   arrayWithNumbers[arrayWithNumbers.length - 1] = suffle[index];
   suffle[index] = temp;
   return +arrayWithNumbers.concat(suffle).join('');

rot13/main.js

@@ -0,0 +1,14 @@
+function rot13(str) {
+  return [...str].reduce((acc, cur) => {
+    const charCode = cur.toUpperCase().charCodeAt(0) - 65;
+    return ((0 <= charCode && charCode <= 25) ? acc += String.fromCharCode(cur.charCodeAt(0) + (charCode >= 13 ? -13 : 13)) : acc += cur, acc);
+
+    /// Readable
+    let operator = 0; 
+    if(0 <= charCode && charCode <= 25) operator = charCode >= 13 ? -13 : 13;
+    acc += String.fromCharCode(cur.charCodeAt(0) + operator);
+    return acc;
+  }, '');
+}
+
+module.exports = rot13;

rot13/main.test.js

@@ -0,0 +1,63 @@
+const rot13 = require('./main');
+
+describe('13 rotation tests with one letter', () => {
+  test('a returns n', () => {
+    expect(rot13('a')).toBe('n');
+  });
+
+  test('b returns o', () => {
+    expect(rot13('b')).toBe('o');
+  });
+
+  test('c returns p', () => {
+    expect(rot13('c')).toBe('p');
+  });
+});
+
+describe('13 rotation tests with more than one letter', () => {
+  test('ab returns no', () => {
+    expect(rot13('ab')).toBe('no');
+  });
+
+  test('fl returns sy', () => {
+    expect(rot13('fl')).toBe('sy');
+  });
+
+  test('hello returns uryyb', () => {
+    expect(rot13('hello')).toBe('uryyb');
+  });
+});
+
+describe('13 rotation tests with capital letter', () => {
+  test('A returns N', () => {
+    expect(rot13('A')).toBe('N');
+  });
+
+  test('AN returns NA', () => {
+    expect(rot13('AN')).toBe('NA');
+  });
+});
+
+describe('13 rotation ignores spaces and punctuation, numbers, etc', () => {
+  test('A C returns N P', () => {
+    expect(rot13('A C')).toBe('N P');
+  });
+
+  test('..." returns EBG13 ...', () => {
+    expect(rot13('...')).toBe('...');
+  });
+
+  test('@# $ %." returns @# $ %.', () => {
+    expect(rot13('@# $ %.')).toBe('@# $ %.');
+  });
+});
+
+describe('13 rotation tests with all combinations', () => {
+  test('ROT13 example. returns EBG13 rknzcyr.', () => {
+    expect(rot13('ROT13 example.')).toBe('EBG13 rknzcyr.');
+  });
+
+  test('This is my first ROT13 excercise! returns Guvf vf zl svefg EBG13 rkprepvfr!', () => {
+    expect(rot13('This is my first ROT13 excercise!')).toBe('Guvf vf zl svefg EBG13 rkprepvfr!');
+  });
+});