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/**
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 * @param {number[]} piles
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 * @return {number}
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 */
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var stoneGameII = function (piles) {
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  let sum = 0;
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  const dp = new Array(101).fill(0).map(() => new Array(201).fill(0));
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  for (let i = 0; i < piles.length; i++) {
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    sum += piles[i];
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  }
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  let diff = help(0, 1, piles, dp);
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  return (sum + diff) / 2;
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};
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function help(i, M, piles, dp) {
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  if (i >= piles.length) return 0;
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  if (dp[i][M] != 0) return dp[i][M];
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  let total = 0;
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  let ans = Number.MIN_SAFE_INTEGER;
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  for (let j = 0; j < 2 * M; j++) {
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    if (i + j < piles.length) total += piles[i + j];
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    ans = Math.max(ans, total - help(i + j + 1, Math.max(M, j + 1), piles, dp));
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  }
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  dp[i][M] = ans;
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  return ans;
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}