Knight Dialer LeetCode solution in JavaScript

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var knightDialer = function (n) {
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  let dp = Array(10).fill(1);
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  let MOD = 10 ** 9 + 7;
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  for (let i = 2; i <= n; i++) {
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    oldDp = [...dp];
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    dp[0] = (oldDp[4] + oldDp[6]) % MOD;
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    dp[1] = (oldDp[8] + oldDp[6]) % MOD;
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    dp[2] = (oldDp[9] + oldDp[7]) % MOD;
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    dp[3] = (oldDp[8] + oldDp[4]) % MOD;
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    dp[4] = (oldDp[3] + oldDp[9] + oldDp[0]) % MOD;
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    dp[5] = 0;
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    dp[6] = (oldDp[0] + oldDp[7] + oldDp[1]) % MOD;
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    dp[7] = (oldDp[6] + oldDp[2]) % MOD;
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    dp[8] = (oldDp[3] + oldDp[1]) % MOD;
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    dp[9] = (oldDp[4] + oldDp[2]) % MOD;
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  }
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  return dp.reduce((ans, ele) => (ans += ele), 0) % MOD;
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};