Method STM

Data Structures/Segment Tree Merging.cpp:14–17

  int T;
  int id[N * 30];
  STM() {
    T = 0;
    for (int i = 1; i < N * 30; i++) id[i] = i;
  }
  inline int new_node() {
    int cur = id[++T];
    t[cur].l = t[cur].r = t[cur].sz = 0;