警钟长鸣！！！（仅AC#1#3

void make_tag2(ll x) {
  w += x;
  t1 += x;
  t2 += x;
}

void make_tag2(ll x) {
  w += x;
  if (t1 != nul)
    t1 += x;
  else
    t2 += x;
}