feat(other): add count_values

Author: Rudxain

other/count_values.ts

@@ -0,0 +1,19 @@
+export const countValues = <T>(it: Iterable<T>) => {
+  const counts: Map<T, bigint> = new Map()
+  for (const x of it) {
+    counts.set(x, (counts.get(x) ?? 0n) + 1n)
+  }
+  return counts
+}
+
+export const countValuesNew = <T>(a: Iterable<T>) =>
+  Iterator.from(a).reduce(
+    (counts, x) => counts.set(x, (counts.get(x) ?? 0n) + 1n),
+    new Map<T, bigint>()
+  )
+
+export const countValuesBounded = <T>(a: readonly T[]) =>
+  a.reduce(
+    (counts, x) => counts.set(x, (counts.get(x) ?? 0) + 1),
+    new Map<T, number>()
+  )