#include <fstream>
#include <algorithm>
#include <vector>
#define N 200010
#define mp make_pair
#define f first
#define s second
using namespace std;

int Mc[N], Mx[N], My[N], ind[N], inq[N], P[N], n, m, q, x, y, c, nod, k, total, nr[N], Q[N];
vector<pair<int, int> > :: iterator it;
vector<pair<int, int> > v[N], u;
bool ok;

bool cmp(int x, int y)
{
    return Mc[x] > Mc[y];
}

bool cmp2(pair<int, int> x, pair<int, int> y)
{
    return x.f < y.f;
}

void merge_vectors(vector<pair<int, int> > v1, vector<pair<int, int> > v2)
{
    int i, j, n1, n2;
    n1 = v1.size();
    n2 = v2.size();
    for(i = 0, j = 0; i < n1 or j < n2; )
    {
        if(i < n1 and i < n2 and v1[i].f < v2[j].f) u.push_back(v1[i]), i++; else
        if(i < n1 and i < n2 and v1[i].f >= v2[j].f) u.push_back(v2[j]), j++; else
        if(i < n1) u.push_back(v1[i]), i++; else u.push_back(v2[j]), j++;
    }
}

int comp(int x)
{
    if(P[x] == x) return x;
    return P[x] = comp(P[x]);
}

void reunite(int x, int y)
{
    P[comp(x)] = comp(y);
}

int main()
{
    int i;
    ifstream fi("luff.in");
    ofstream fo("luff.out");
    fi >> n >> m >> q;
    for(i = 1; i <= m; i++)
    {
        fi >> x >> y >> c;
        Mx[i] = x; My[i] = y; Mc[i] = c; ind[i] = i;
    }
    for(i = 1; i <= q; i++)
    {
        fi >> nod >> k;
        inq[nod] = 1;
        v[nod].push_back(mp(k, i));
    }
    for(i = 1; i <= n; i++) sort(v[i].begin(), v[i].end(), cmp2);
    for(i = 1; i <= n; i++)
    {
        P[i] = i;
        nr[i] = 1;
    }
    sort(ind+1, ind+m+1, cmp);
    for(i = 1; i <= m; i++)
        if(comp(Mx[ind[i]]) != comp(My[ind[i]]))
        {
            x = Mx[ind[i]]; y = My[ind[i]];
            merge_vectors(v[comp(x)], v[comp(y)]);
            total = nr[comp(x)] + nr[comp(y)];
            ok = 0;
            if(inq[comp(x)] or inq[comp(y)]) ok = 1;
            reunite(x, y);
            c = comp(x);
            if(ok)
            {
                inq[x] = inq[y] = 0;
                inq[c] = 1;
            }
            nr[c] = total;
            v[c] = u;
            for(it = v[c].begin(); it != v[c].end();)
                if(it->f <= nr[c])
                {
                    ++it;
                    Q[it->s] = Mc[ind[i]];
                    v[c].erase(v[c].begin());
                } else ++it;
            //verific daca nu cumva am indeplinit un query
        }
    return 0;
}