new exercise

lab/exercises/10-mixed/even-first.js

@@ -0,0 +1,14 @@
+function evenFirst(array) {
+  let lo = 0;
+  let hi = 1;
+  while (hi < array.length) {
+    if (array[hi] % 2 === 0) {
+      [array[hi], array[lo]] = [array[lo], array[hi]];
+      lo++;
+    }
+    hi++;
+  }
+  return array;
+}
+
+module.exports = evenFirst;

lab/exercises/10-mixed/even-first.spec.js

@@ -0,0 +1,9 @@
+const fn = require('./even-first');
+
+describe('Sort even first and then odd', () => {
+  it('should work', () => {
+    const actual = fn([5, 4, 3, 7, 8, 3, 2]);
+    expect(actual.slice(0, 3)).toEqual(expect.arrayContaining([4, 8, 2]));
+    expect(actual.slice(3)).toEqual(expect.arrayContaining([5, 3, 7, 3]));
+  });
+});