Description：

Solution：

Code：

#include<algorithm>

#include<iostream>

#include<cstdlib>

#include<cstdio>

#include<cmath>

#include<cctype>

#include<cstring>

using namespace std;

#define R register

inline int rd()

{

	R int res = 0,f = 1;

	R char c = getchar();

	while(!isdigit(c))

	{

		if(c == '-')f = -1;

		c = getchar();

	}

	while(isdigit(c))

	{

		res = (res << 1) + (res << 3) + c - '0';

		c = getchar();

	}

	return res * f;

}

int n,m,s;

#define MAXN 100010

int h[MAXN];

#define MAXM 500010

struct edges

{

	int u,v,w;

}es[MAXM];

bool cmp_w(edges a,edges b){return a.w < b.w;}

struct query

{

	int p,x,k,id;

}q[MAXM];

bool cmp_x(query a,query b){return a.x < b.x;}

int ans[MAXM];

struct node

{

	int lc,rc;

	int sum;

}t[MAXN * 33];

int ptr = 0;

int newnode(){return ++ptr;}

#define LE 0

#define RI 1000000000

#define mid ((l + r) >> 1)

int root[MAXN];

void insert(int &rt,int p,int l,int r)

{

	rt = newnode();

	++t[rt].sum;

	if(l == r)return;

	if(p <= mid)insert(t[rt].lc,p,l,mid);

	else insert(t[rt].rc,p,mid + 1,r);

	return;

}

int merge(int rtx,int rty,int l,int r)

{

	if(rtx == 0 || rty == 0)return rtx + rty;

	t[rtx].sum += t[rty].sum;

	if(l == r)return rtx;

	t[rtx].lc = merge(t[rtx].lc,t[rty].lc,l,mid);

	t[rtx].rc = merge(t[rtx].rc,t[rty].rc,mid + 1,r);

	return rtx;

}

int query(int rt,int k,int l,int r)

{

	if(rt == 0)return -1;

	if(t[rt].sum < k)return -1;

	if(l == r)return l;

	if(k <= t[t[rt].rc].sum)return query(t[rt].rc,k,mid + 1,r);

	else return query(t[rt].lc,k - t[t[rt].rc].sum,l,mid);

}

int f[MAXN];

int find(int x){return (x == f[x] ? x : f[x] = find(f[x]));}

inline void collect(int a,int b)

{

	int p = find(a),q = find(b);

	if(p == q)return;

	f[p] = q;

	root[q] = merge(root[p],root[q],LE,RI);

	return;

}

int main()

{

	scanf("%d%d%d",&n,&m,&s);

	for(R int i = 1;i <= n;++i)h[i] = rd();

	for(R int i = 1;i <= n;++i)f[i] = i;

	for(R int i = 1;i <= m;++i)

	{

		es[i].u = rd();es[i].v = rd();es[i].w = rd();

	}

	sort(es + 1,es + 1 + m,cmp_w);

	for(R int i = 1;i <= s;++i)

	{

		q[i].p = rd();q[i].x = rd();q[i].k = rd();

		q[i].id = i;

	}

	for(R int i = 1;i <= n;++i)insert(root[i],h[i],LE,RI);

	sort(q + 1,q + 1 + s,cmp_x);

	for(R int i = 1,j = 1;i <= s;++i)

	{

		while(j <= m && es[j].w <= q[i].x)

		{

			collect(es[j].u,es[j].v);

			++j;

		}

		ans[q[i].id] = query(root[find(q[i].p)],q[i].k,LE,RI);

	}

	for(R int i = 1;i <= s;++i)printf("%d\n",ans[i]);

	return 0;

}