Help!

Правка en5, от DEAMN, 2021-04-19 10:39:42

  • I can't think of a DP for this task help plz Find the number of sequences (a1, a2,..., an) such that a[i]^2 + a[i + 1]^2 + ... + a[n]^2 = k a[i] <= a[i + 1] <= ... <= a[n]

  • T is testcase

  • n is quantity of number
  • k is a[i]^2 + a[i + 1]^2 + ... + a[n]^2 = k

  • 1 <= T <= 1e5

  • 1 <= n <= 100
  • 1 <= k <= 5000
  • example
  • input
  • 1
  • 4 243
  • output
  • 9

  • Explanation

  • first 1 1 4 15 -> (1 * 1) + (1 * 1) + (4 * 4) + (15 * 15) = 243 — second 1 3 8 13 — third 1 7 7 12 — fouth 3 3 9 12 — fifth 3 4 7 13 — sixth 3 7 8 11 — seventh 4 5 9 11 — eighth 5 5 7 12 — nineth 7 7 8 9

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  Rev. Язык Кто Когда Δ Комментарий
en5 Английский DEAMN 2021-04-19 10:39:42 1
en4 Английский DEAMN 2021-04-19 09:57:26 136
en3 Английский DEAMN 2021-04-19 09:54:55 51
en2 Английский DEAMN 2021-04-19 09:52:44 62 Tiny change: '**I can't ' -> '- **I can't '
en1 Английский DEAMN 2021-04-19 09:50:35 1774 Initial revision (published)