type-challenges#5423 - Intersection (type-challenges#5424)

Co-authored-by: Pineapple <[email protected]>

questions/5423-hard-intersection/README.md

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+Implement the type version of Lodash.intersection, but there is a little different, Intersection<T> takes an Array T containing several arrays or any type element that includes the union type, returns a new array containing all incoming array intersection elements.
+
+```ts
+type Res = Intersection<[[1, 2], [2, 3], [2, 2]]>; // expected to be 2
+type Res1 = Intersection<[[1, 2, 3], [2, 3, 4], [2, 2, 3]]>; // expected to be 2 | 3
+type Res2 = Intersection<[[1, 2], [3, 4], [5, 6]]>; // expected to be never
+type Res3 = Intersection<[[1, 2, 3], [2, 3, 4], 3]>; // expected to be 3
+type Res4 = Intersection<[[1, 2, 3], 2 | 3 | 4, 2 | 3]>; // expected to be 2 | 3
+type Res5 = Intersection<[[1, 2, 3], 2, 3]>; // expected to be never
+```

questions/5423-hard-intersection/info.yml

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+difficulty: hard
+title: Intersection
+tags: union, array
+author:
+  github: Pineapple0919
+  name: Pineapple
+

questions/5423-hard-intersection/template.ts

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+type Intersection<T> = any

questions/5423-hard-intersection/test-cases.ts

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+import { Equal, Expect } from '@type-challenges/utils'
+
+type cases = [
+  Expect<Equal<Intersection<[[1, 2], [2, 3], [2, 2]]>, 2>>,
+  Expect<Equal<Intersection<[[1, 2, 3], [2, 3, 4], [2, 2, 3]]>, 2 | 3>>,
+  Expect<Equal<Intersection<[[1, 2], [3, 4], [5, 6]]>, never>>,
+  Expect<Equal<Intersection<[[1, 2, 3], [2, 3, 4], 3]>, 3>>,
+  Expect<Equal<Intersection<[[1, 2, 3], 2 | 3 | 4, 2 | 3]>, 2 | 3>>,
+  Expect<Equal<Intersection<[[1, 2, 3], 2, 3]>, never>>
+]