feat: without

src/05117-medium-without.ts

@@ -0,0 +1,25 @@
+// ============= Test Cases =============
+import type { Equal, Expect } from './test-utils'
+
+type cases = [
+  Expect<Equal<Without<[1, 2], 1>, [2]>>,
+  Expect<Equal<Without<[1, 2, 4, 1, 5], [1, 2]>, [4, 5]>>,
+  Expect<Equal<Without<[2, 3, 2, 3, 2, 3, 2, 3], [2, 3]>, []>>
+]
+
+// ============= Your Code Here =============
+
+type ArrayToUnion<T extends number | number[]> = T extends number[]
+  ? T[number]
+  : T
+
+/** 遇到`U`可能是数组或数字的情况下，把数组转成Union类型，然后使用extends作为条件就很方便处理 */
+type Without<
+  T,
+  U extends number | number[],
+  Result extends any[] = []
+> = T extends [infer F, ...infer R]
+  ? F extends ArrayToUnion<U>
+    ? Without<R, U, Result>
+    : Without<R, U, [...Result, F]>
+  : Result