// start A.cpp // #pragma GCC target("avx2") // #pragma GCC optimize("O3") // #pragma GCC optimize("unroll-loops") #include using namespace std; using ll = long long; using ull = unsigned long long; template using pq = priority_queue; template using qp = priority_queue, greater>; #define vec(T, A, ...) vector A(__VA_ARGS__); #define vvec(T, A, h, ...) vector> A(h, vector(__VA_ARGS__)); #define vvvec(T, A, h1, h2, ...) vector>> A(h1, vector>(h2, vector(__VA_ARGS__))); #ifndef RIN__LOCAL #define endl "\n" #endif #define spa ' ' #define len(A) A.size() #define all(A) begin(A), end(A) #define fori1(a) for (ll _ = 0; _ < (a); _++) #define fori2(i, a) for (ll i = 0; i < (a); i++) #define fori3(i, a, b) for (ll i = (a); i < (b); i++) #define fori4(i, a, b, c) for (ll i = (a); ((c) > 0 || i > (b)) && ((c) < 0 || i < (b)); i += (c)) #define overload4(a, b, c, d, e, ...) e #define fori(...) overload4(__VA_ARGS__, fori4, fori3, fori2, fori1)(__VA_ARGS__) vector stoc(string &S) { int n = S.size(); vector ret(n); for (int i = 0; i < n; i++) ret[i] = S[i]; return ret; } #define INT(...) \ int __VA_ARGS__; \ inp(__VA_ARGS__); #define LL(...) \ ll __VA_ARGS__; \ inp(__VA_ARGS__); #define STRING(...) \ string __VA_ARGS__; \ inp(__VA_ARGS__); #define CHAR(...) \ char __VA_ARGS__; \ inp(__VA_ARGS__); #define VEC(T, A, n) \ vector A(n); \ inp(A); #define VVEC(T, A, n, m) \ vector> A(n, vector(m)); \ inp(A); const ll MOD1 = 1000000007; const ll MOD9 = 998244353; template auto min(const T &a) { return *min_element(all(a)); } template auto max(const T &a) { return *max_element(all(a)); } template auto clamp(T &a, const S &l, const S &r) { return (a > r ? r : a < l ? l : a); } template inline bool chmax(T &a, const S &b) { return (a < b ? a = b, 1 : 0); } template inline bool chmin(T &a, const S &b) { return (a > b ? a = b, 1 : 0); } template inline bool chclamp(T &a, const S &l, const S &r) { auto b = clamp(a, l, r); return (a != b ? a = b, 1 : 0); } void FLUSH() { cout << flush; } void print() { cout << endl; } template void print(Head &&head, Tail &&... tail) { cout << head; if (sizeof...(Tail)) cout << spa; print(forward(tail)...); } template void print(vector &A) { int n = A.size(); for (int i = 0; i < n; i++) { cout << A[i]; if (i != n - 1) cout << ' '; } cout << endl; } template void print(vector> &A) { for (auto &row : A) print(row); } template void print(pair &A) { cout << A.first << spa << A.second << endl; } template void print(vector> &A) { for (auto &row : A) print(row); } template void prisep(vector &A, S sep) { int n = A.size(); for (int i = 0; i < n; i++) { cout << A[i]; if (i != n - 1) cout << sep; } cout << endl; } template void priend(T A, S end) { cout << A << end; } template void priend(T A) { priend(A, spa); } template void inp(T &... a) { (cin >> ... >> a); } template void inp(vector &A) { for (auto &a : A) cin >> a; } template void inp(vector> &A) { for (auto &row : A) inp(row); } template void inp(pair &A) { inp(A.first, A.second); } template void inp(vector> &A) { for (auto &row : A) inp(row.first, row.second); } template T sum(vector &A) { T tot = 0; for (auto a : A) tot += a; return tot; } template vector compression(vector X) { sort(all(X)); X.erase(unique(all(X)), X.end()); return X; } vector> read_edges(int n, int m, bool direct = false, int indexed = 1) { vector> edges(n, vector()); for (int i = 0; i < m; i++) { INT(u, v); u -= indexed; v -= indexed; edges[u].push_back(v); if (!direct) edges[v].push_back(u); } return edges; } vector> read_tree(int n, int indexed = 1) { return read_edges(n, n - 1, false, indexed); } template vector>> read_wedges(int n, int m, bool direct = false, int indexed = 1) { vector>> edges(n, vector>()); for (int i = 0; i < m; i++) { INT(u, v); T w; inp(w); u -= indexed; v -= indexed; edges[u].push_back({v, w}); if (!direct) edges[v].push_back({u, w}); } return edges; } template vector>> read_wtree(int n, int indexed = 1) { return read_wedges(n, n - 1, false, indexed); } bool yes(bool f = true) { cout << (f ? "yes" : "no") << endl; return f; } bool Yes(bool f = true) { cout << (f ? "Yes" : "No") << endl; return f; } bool YES(bool f = true) { cout << (f ? "YES" : "NO") << endl; return f; } bool no(bool f = false) { cout << (!f ? "yes" : "no") << endl; return f; } bool No(bool f = false) { cout << (!f ? "Yes" : "No") << endl; return f; } bool NO(bool f = false) { cout << (!f ? "YES" : "NO") << endl; return f; } // start data_structure/UnionFind.hpp struct UnionFind { int n; vector par; int group; UnionFind() = default; UnionFind(int n) : n(n) { par.assign(n, -1); group = n; } int find(int x) { if (par[x] < 0) return x; par[x] = find(par[x]); return par[x]; } bool unite(int x, int y) { x = find(x); y = find(y); if (x == y) return false; if (par[x] > par[y]) swap(x, y); group--; par[x] += par[y]; par[y] = x; return true; } bool same(int x, int y) { return find(x) == find(y); } int size(int x) { return -par[find(x)]; } vector roots() { vector ret; for (int i = 0; i < n; i++) { if (i == find(i)) ret.push_back(i); } return ret; } }; // end data_structure/UnionFind.hpp // restart A.cpp void solve() { INT(n, Q); VEC(int, P, n); UnionFind UF(n); fori(i, n) { if (P[i] != -1) UF.unite(i, P[i] - 1); } fori(Q) { INT(a, b); Yes(UF.same(a - 1, b - 1)); } } int main() { cin.tie(0)->sync_with_stdio(0); // cout << fixed << setprecision(12); int t; t = 1; // cin >> t; while (t--) solve(); return 0; } // end A.cpp