message: Update stone-game-vii.cpp
diff: // Time: O(n^2)
  -// Space: O(n^2)
  +// Space: O(n)
  class Solution {
  public:
  @@ -11,11 +11,11 @@ public:
  const auto& score = [&prefix](int i, int j) {
  return prefix[j + 1] - prefix[i];
  };
  - vector<vector<int>> dp(size(stones) , vector<int>(size(stones)));
  + vector<vector<int>> dp(2, vector<int>(size(stones)));
  for (int i = size(stones) - 1; i >= 0; --i) {
  for (int j = i + 1; j < size(stones); ++j) {
  - dp[i][j] = max(score(i + 1, j) - dp[i + 1][j],
  - score(i, j - 1) - dp[i][j - 1]);
  + dp[i % 2][j] = max(score(i + 1, j) - dp[(i + 1) % 2][j],
  + score(i, j - 1) - dp[i % 2][j - 1]);
  }
  }
  return dp[0][size(stones) - 1];
  