#include #pragma GCC optimize("O3") #pragma GCC target("sse4") using namespace std; using HashSet = unordered_set; using FewCounter = unordered_map>; signed main() { int N, M, Q; cin >> N >> M; int K = sqrt(M); vector world(N+1); // world[i] = the world that person i is in FewCounter num_few_of; // num_few_of[i].at(w) = # friends of i in world j with < K friends vector many; // many = [those with >= K friends] vector friends(N+1); auto is_many = [&] (int i) { return friends[i].size() >= K; }; for (int i = 1; i <= N; ++i) cin >> world[i]; for (int i = 1; i <= M; ++i) { int a, b; cin >> a >> b; friends[a].insert(b); friends[b].insert(a); } for (int i = 1; i <= N; ++i) { if (!is_many(i)) continue; many.push_back(i); num_few_of[i].assign(N+1, 0); for (int f : friends[i]) if (!is_many(f)) { int w = world[f]; ++num_few_of[i].at(w); } } auto solve_many = [&] (int x, int y) { int new_world = world[y]; if (num_few_of[x].at(new_world) > 0) goto success; for (int m : many) if (friends[x].count(m) && world[m] == new_world) goto success; return "No\n"; success: world[x] = new_world; return "Yes\n"; }; auto solve_few = [&] (int x, int y) { for (int f : friends[x]) if (world[f] == world[y]) goto success; return "No\n"; success: int old_world = world[x]; int new_world = world[y]; for (int f : friends[x]) { if (is_many(f)) continue; --num_few_of[f].at(old_world); ++num_few_of[f].at(new_world); } world[x] = new_world; return "Yes\n"; }; cin >> Q; while (Q--) { int x, y; cin >> x >> y; if (world[x] == world[y]) { cout << "No\n"; continue; } auto ans = is_many(x) ? solve_many(x,y) : solve_few(x,y); cout << ans; } }