1. #include <bits/stdc++.h>
  2. using namespace std;
  3.  
  4. #define IOS ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);
  5. #define endl "\n"
  6. #define int long long
  7.  
  8. const int N = 111115;
  9. const int LG = log2(N) + 1;
  10.  
  11. int n, q, ct = 0, num = 0;
  12. int a[N], root[N], level[N];
  13. int st[21*N], lc[21*N], rc[21*N];
  14. int tim=0;
  15. int parent[LG][N];
  16. map<int, int> comp, rcomp;
  17. vector<int> g[N];
  18.  
  19. void dfs0(int k, int par, int lvl)
  20. {
  21. 	parent[0][k] = par;
  22. 	level[k] = lvl;
  23. 	for(auto it:g[k])
  24. 	{
  25. 		if(it==par)
  26. 			continue;
  27. 		dfs0(it, k, lvl+1);
  28. 	}
  29. }
  30.  
  31. void precompute()
  32. {
  33. 	for(int i=1;i<LG;i++)
  34. 		for(int j=1;j<=n;j++)
  35. 			if(parent[i-1][j])
  36. 				parent[i][j]=parent[i-1][parent[i-1][j]];
  37. }
  38.  
  39. int LCA(int u, int v)
  40. {
  41. 	if(level[u]<level[v])
  42. 		swap(u,v);
  43. 	int diff=level[u]-level[v];
  44. 	for(int i=LG-1;i>=0;i--)
  45. 	{
  46. 		if((1<<i) & diff)
  47. 		{
  48. 			u=parent[i][u];
  49. 		}
  50. 	}
  51. 	if(u==v)
  52. 		return u;
  53. 	for(int i=LG-1;i>=0;i--)
  54. 	{
  55. 		if(parent[i][u] && parent[i][u]!=parent[i][v])
  56. 		{
  57. 			u=parent[i][u];
  58. 			v=parent[i][v];
  59. 		}
  60. 	}
  61. 	return parent[0][u];
  62. }
  63.  
  64.  
  65. int build(int L, int R)
  66. {
  67. 	int node = ++ct;
  68. 	if(L==R)
  69. 		return node;
  70. 	int M = (L+R)/2;
  71. 	lc[node] = build(L, M);
  72. 	rc[node] = build(M+1, R);
  73. 	return node;
  74. }
  75.  
  76. int update(int onode, int L, int R, int pos)
  77. {
  78. 	int node = ++ct;
  79. 	if(L==R)
  80. 	{
  81. 		st[node] = st[onode] + 1;
  82. 		return node;
  83. 	}
  84. 	int M = (L+R)/2;
  85. 	lc[node] = lc[onode];
  86. 	rc[node] = rc[onode];
  87. 	if(pos <= M)
  88. 		lc[node] = update(lc[onode], L, M, pos);
  89. 	else
  90. 		rc[node] = update(rc[onode], M+1, R, pos);
  91. 	st[node] = st[lc[node]] + st[rc[node]];
  92. 	return node;
  93. }
  94.  
  95. int query(int nodeu, int nodev, int nodelca, int nodelcapar, int L, int R, int pos)
  96. {
  97. 	if(L==R)
  98. 		return L;
  99. 	int M = (L+R)/2;
  100. 	int leftval = st[lc[nodeu]] + st[lc[nodev]] - st[lc[nodelca]] - st[lc[nodelcapar]];
  101. 	int rightval = st[rc[nodeu]] + st[rc[nodev]] - st[rc[nodelca]] - st[rc[nodelcapar]];
  102. 	if(leftval>=pos)
  103. 		return query(lc[nodeu], lc[nodev], lc[nodelca], lc[nodelcapar], L, M, pos);
  104. 	else
  105. 		return query(rc[nodeu], rc[nodev], rc[nodelca], rc[nodelcapar], M+1, R, pos-leftval);
  106. }
  107.  
  108. void dfs(int u, int par)
  109. {
  110. 	int onode = root[par];
  111. 	root[u] = update(onode, 1, num, a[u]);
  112. 	for(auto &it:g[u])
  113. 	{
  114. 		if(it==par)
  115. 			continue;
  116. 		dfs(it, u);
  117. 	}
  118. }
  119.  
  120. int32_t main()
  121. {
  122. 	IOS;
  123. 	cin>>n>>q;
  124. 	for(int i=1;i<=n;i++)
  125. 	{
  126. 		cin>>a[i];
  127. 		comp[a[i]];
  128. 	}
  129. 	for(auto &it:comp)
  130. 	{
  131. 		it.second = ++num;
  132. 		rcomp[num] = it.first;
  133. 	}
  134. 	for(int i=1;i<=n;i++)
  135. 		a[i] = comp[a[i]];
  136. 	for(int i=1;i<=n-1;i++)
  137. 	{
  138. 		int u, v;
  139. 		cin>>u>>v;
  140. 		g[u].push_back(v);
  141. 		g[v].push_back(u);
  142. 	}
  143. 	root[0] = build(1, num);
  144. 	dfs0(1, 0, 1);
  145. 	precompute();
  146. 	dfs(1, 0);
  147. 	while(q--)
  148. 	{
  149. 		int u, v, k;
  150. 		cin>>u>>v>>k;
  151. 		int lca = LCA(u, v);
  152. 		int parlca = parent[0][lca];
  153. 		int value = query(root[u], root[v], root[lca], root[parlca], 1, num, k);
  154. 		int ans = rcomp[value];
  155. 		cout<<ans<<endl;
  156. 	}
  157. 	return 0;
  158. }
  159.