#include <bits/stdc++.h>
using namespace std;
#define int long long
const int MN = 1e5+5;
int n, m, q, ans;
vector<tuple<int, int, int>> edges;
int par[MN], sz[MN];
bool ok[MN];
int find(int u) {
if (par[u] == u) return u;
return par[u] = find(par[u]);
}
void merge(int u, int v) {
u = find(u);
v = find(v);
if (u == v) return;
if (sz[u] > sz[v]) swap(u, v);
par[u] = v;
sz[v] += sz[u];
ok[v] |= ok[u];
}
void solve() {
cin >> n >> m >> q;
for (int i = 1; i <= m; i++) {
int u, v, c; cin >> u >> v >> c;
u++;
v++;
edges.push_back({c, u, v});
}
sort(edges.begin(), edges.end());
while (q--) {
ans = 0;
int l, r; cin >> l >> r;
l++;
r++;
for (int i = 1; i <= n; i++) {
ok[i] = false;
par[i] = i;
sz[i] = 1;
if (i >= l && i <= r) ok[i] = true;
}
for (auto [c, u, v]: edges) {
u = find(u);
v = find(v);
if (u == v || (ok[u] && ok[v])) continue;
ans += c;
merge(u, v);
}
cout << ans << "\n";
}
}
signed main() {
ios_base::sync_with_stdio(0);
cin.tie(0);
solve();
return 0;
}
