Node getMax(int a, int b, int add){
  Node ret = LOS;
  while(dad[a] != dad[b]){
    if(depth[dad[a]] > depth[dad[b]]) swap(a, b);
    ret = kombaj(ret, query(1, 0, timer - 1, pos[dad[b]], pos[b]));
    b = parent[dad[b]];
  }
  if(depth[a] > depth[b]) swap(a, b);
  ret = kombaj(ret, query(1, 0, timer - 1, pos[a] + add, pos[b]));
  return ret;
}

void upd(int a, int b, int x){
  while(dad[a] != dad[b]){
    if(depth[dad[a]] > depth[dad[b]]) swap(a, b);
    update(1, 0, timer - 1, pos[dad[b]], pos[b], x);
    b = parent[dad[b]];
  }
  if(depth[a] > depth[b]) swap(a, b);
  update(1, 0, timer - 1, pos[a], pos[b], x);
}

  while(q--){
    int t, a, b; scanf("%d %d %d", &t, &a, &b);
    int lca = getLca(a, b);
    if(t == 1){
      Node lef = getMax(lca, a, 0);
      Node rig = getMax(lca, b, 1);
      ll sol = kombaj(lef, rig).best;
      printf("%lld\n", sol);
    }
    else{
      int x; scanf("%d", &x);
      upd(a, b, x);
    }
  }