#line 2 "/home/cocojapanpan/Procon_CPP/proconLibrary/lib/template/procon.hpp" #ifndef DEBUG // 提出時にassertはオフ #ifndef NDEBUG #define NDEBUG #endif // 定数倍高速化 #pragma GCC target("avx2") #pragma GCC optimize("O3") #pragma GCC optimize("unroll-loops") #endif #include <bits/stdc++.h> using namespace std; using ll = long long; #define ALL(x) (x).begin(), (x).end() template <class T> using vec = vector<T>; template <class T, class S> inline bool chmax(T &a, const S &b) { return (a < b ? a = b, 1 : 0); } template <class T, class S> inline bool chmin(T &a, const S &b) { return (a > b ? a = b, 1 : 0); } template <class T> constexpr T INF = 1'000'000'000; template <> constexpr int INF<int> = 1'000'000'000; template <> constexpr ll INF<ll> = ll(INF<int>) * INF<int> * 2; #line 2 "main.cpp" #include <atcoder/dsu> int main() { ios_base::sync_with_stdio(false); cin.tie(nullptr); int N, Q; cin >> N >> Q; atcoder::dsu DSU(N); for(int i = 0; i < N; i++) { int p; cin >> p; if(p != -1) { --p; DSU.merge(i, p); } } for(int i = 0; i < Q; i++) { int a, b; cin >> a >> b; --a; --b; cout << (DSU.same(a, b) ? "Yes" : "No") << "\n"; } }