1
var stoneGameV = function (stoneValue) {
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  // Find the stoneValue array's prefix sum
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  let prefix = Array(stoneValue.length).fill(0);
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  for (let i = 0; i < stoneValue.length; i++) {
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    prefix[i] = stoneValue[i] + (prefix[i - 1] || 0);
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  }
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  let dp = Array(stoneValue.length)
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    .fill()
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    .map(() => Array(stoneValue.length).fill(0));
11

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  function game(start, end) {
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    if (dp[start][end]) return dp[start][end];
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    if (start === end) return 0;
15

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    let max = 0;
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    for (let i = start + 1; i <= end; i++) {
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      let sumL = prefix[i - 1] - (prefix[start - 1] || 0);
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      let sumR = prefix[end] - (prefix[i - 1] || 0);
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      if (sumL > sumR) {
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        max = Math.max(max, sumR + game(i, end));
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      } else if (sumL < sumR) {
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        max = Math.max(max, sumL + game(start, i - 1));
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      } else {
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        // If tied, check both rows
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        let left = sumR + game(i, end);
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        let right = sumL + game(start, i - 1);
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        max = Math.max(max, left, right);
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      }
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    }
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    return (dp[start][end] = max);
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  }
33

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  return game(0, stoneValue.length - 1);
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};