2257 - MinusOne

[teamchong]

type MinusOne<T extends number> = CountToT<`${T}`> extends [...infer M1, 1] ? M1['length'] : 0

type CountToT<T extends string> =
  T extends `${infer Prefix extends string}${keyof N}`
    ? N<CountToT<Prefix>>[T extends `${Prefix}${infer D extends keyof N}` ? D : never]
  : []

type N<T extends 1[] = []> = {
  '0': [...T, ...T, ...T, ...T, ...T, ...T, ...T, ...T, ...T, ...T],
  '1': [...T, ...T, ...T, ...T, ...T, ...T, ...T, ...T, ...T, ...T, 1],
  '2': [...T, ...T, ...T, ...T, ...T, ...T, ...T, ...T, ...T, ...T, 1, 1],
  '3': [...T, ...T, ...T, ...T, ...T, ...T, ...T, ...T, ...T, ...T, 1, 1, 1],
  '4': [...T, ...T, ...T, ...T, ...T, ...T, ...T, ...T, ...T, ...T, 1, 1, 1, 1],
  '5': [...T, ...T, ...T, ...T, ...T, ...T, ...T, ...T, ...T, ...T, 1, 1, 1, 1, 1],
  '6': [...T, ...T, ...T, ...T, ...T, ...T, ...T, ...T, ...T, ...T, 1, 1, 1, 1, 1, 1],
  '7': [...T, ...T, ...T, ...T, ...T, ...T, ...T, ...T, ...T, ...T, 1, 1, 1, 1, 1, 1, 1],
  '8': [...T, ...T, ...T, ...T, ...T, ...T, ...T, ...T, ...T, ...T, 1, 1, 1, 1, 1, 1, 1, 1],
  '9': [...T, ...T, ...T, ...T, ...T, ...T, ...T, ...T, ...T, ...T, 1, 1, 1, 1, 1, 1, 1, 1, 1],
}

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