Segment Tree Compress

[LuchoBazz]

Tourist Code

struct SegmTree {
  vector<int> T; int n;
  SegmTree(int n) : T(2 * n, (int)-2e9), n(n) {}
  
  void Update(int pos, int val) {
    for (T[pos += n] = val; pos > 1; pos /= 2)
      T[pos / 2] = max(T[pos], T[pos ^ 1]);
  }
  
  int Query(int b, int e) {
    int res = -2e9;
    for (b += n, e += n; b < e; b /= 2, e /= 2) {
      if (b % 2) res = max(res, T[b++]);
      if (e % 2) res = max(res, T[--e]);
    }
    return res;
  }
};