add: 只出现一次的数字等

test/array/find-common-characters.test.js

@@ -0,0 +1,9 @@
+import { commonChars } from '../../src/array/find-common-characters'
+
+describe('查找常用字符', () => {
+  test('查找常用字符', () => {
+    expect(commonChars(['bella', 'label', 'roller']).sort()).toEqual(['e', 'l', 'l'].sort())
+    expect(commonChars(['cool', 'lock', 'cook']).sort()).toEqual(['c', 'o'].sort())
+    expect(commonChars(['acabcddd', 'bcbdbcbd', 'baddbadb', 'cbdddcac', 'aacbcccd', 'ccccddda', 'cababaab', 'addcaccd']).sort()).toEqual([].sort())
+  })
+})