using System; using static System.Console; using System.Linq; using System.Collections.Generic; class Program { static int NN => int.Parse(ReadLine()); static int[] NList => ReadLine().Split().Select(int.Parse).ToArray(); static int[][] NArr(long n) => Enumerable.Repeat(0, (int)n).Select(_ => NList).ToArray(); public static void Main() { Solve(); } static void Solve() { var c = NList; var (n, m, q) = (c[0], c[1], c[2]); var map = NArr(m); var query = NArr(q); var tree = new List[n]; for (var i = 0; i < tree.Length; ++i) tree[i] = new List(); foreach (var edge in map) { tree[edge[0] - 1].Add(edge[1] - 1); tree[edge[1] - 1].Add(edge[0] - 1); } var g = new SCCGraph(n); var visited = new bool[n]; for (var i = 0; i < n; ++i) if (!visited[i]) DFS(-1, i, tree, g, visited); var sccList = g.SCC(); var groups = new int[n]; for (var i = 0; i < sccList.Length; ++i) { foreach (var e in sccList[i]) groups[e] = i; } var uf = new UnionFindTree(n); foreach (var edge in map) { if (groups[edge[0] - 1] != groups[edge[1] - 1]) uf.Unite(edge[0] - 1, edge[1] - 1); } var ans = new bool[q]; for (var i = 0; i < q; ++i) { ans[i] = uf.IsSameTree(query[i][0] - 1, query[i][1] - 1); } WriteLine(string.Join("\n", ans.Select(f => f ? "Yes" : "No"))); } static void DFS(int prev, int cur, List[] tree, SCCGraph g, bool[] visited) { if (visited[cur]) return; visited[cur] = true; foreach (var next in tree[cur]) { if (prev == next) continue; g.AddEdge(cur, next); DFS(cur, next, tree, g, visited); } } class SCCGraph { private int _n; private List<(int from, int to)> edges; public SCCGraph(int n) { _n = n; edges = new List<(int, int)>(); } public int NumVertices() { return _n; } public void AddEdge(int from, int to) { edges.Add((from, to )); } public (int, int[]) SCCIds() { var g = new CSR(_n, edges); var nowOrd = 0; var groupNum = 0; var visited = new List(_n); var low = new int[_n]; var ord = Enumerable.Repeat(-1, _n).ToArray(); var ids = new int[_n]; void DFS(int v) { low[v] = ord[v] = nowOrd++; visited.Add(v); for (var i = g.Start[v]; i < g.Start[v + 1]; ++i) { var to = g.EList[i]; if (ord[to] == -1) { DFS(to); low[v] = Math.Min(low[v], low[to]); } else low[v] = Math.Min(low[v], ord[to]); } if (low[v] == ord[v]) { while (true) { var u = visited.Last(); visited.RemoveAt(visited.Count - 1); ord[u] = _n; ids[u] = groupNum; if (u == v) break; } ++groupNum; } } for (var i = 0; i < _n; ++i) if (ord[i] == -1) DFS(i); for (var i = 0; i < ids.Length; ++i) ids[i] = groupNum - 1 - ids[i]; return (groupNum, ids); } public List[] SCC() { var (groupNum, list) = SCCIds(); var counts = new int[groupNum]; foreach (var x in list) ++counts[x]; var groups = new List[groupNum]; for (var i = 0; i < groups.Length; ++i) groups[i] = new List(counts[i]); for (var i = 0; i < _n; ++i) groups[list[i]].Add(i); return groups; } } // 有向辺のリスト class CSR { public int[] Start { get; private set; } public E[] EList { get; private set; } public CSR(int n, List<(int, E)> edges) { Start = new int[n + 1]; EList = new E[edges.Count]; foreach (var e in edges) ++Start[e.Item1 + 1]; for (var i = 1; i <= n; ++i) Start[i] += Start[i - 1]; var counter = (int[])Start.Clone(); foreach (var e in edges) { EList[counter[e.Item1]++] = e.Item2; } } } class UnionFindTree { int[] roots; public UnionFindTree(int size) { roots = new int[size]; for (var i = 0; i < size; ++i) roots[i] = -1; } public int GetRoot(int a) { if (roots[a] < 0) return a; return roots[a] = GetRoot(roots[a]); } public bool IsSameTree(int a, int b) { return GetRoot(a) == GetRoot(b); } public bool Unite(int a, int b) { var x = GetRoot(a); var y = GetRoot(b); if (x == y) return false; if (-roots[x] < -roots[y]) { var tmp = x; x = y; y = tmp; } roots[x] += roots[y]; roots[y] = x; return true; } public int GetSize(int a) { return -roots[GetRoot(a)]; } } }