#include <iostream>
#include <vector>
#include <algorithm>

using namespace std;

vector<vector<int>> graph;
int n, m;

void FW() {
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < n; j++) {
            for (int h = 0; h < n; h++) {
                if ((graph[j][i] != INT_MAX) && (graph[i][h] != INT_MAX)) {
                    graph[j][h] = min(graph[j][h], graph[j][i] + graph[i][h]);
                }
            }
        }
    }
}

int main()
{
    freopen("input.txt", "r", stdin);
    freopen("output.txt", "w", stdout);
    cin >> n >> m;
    graph.resize(n, vector<int>(n, INT_MAX));
    for (int i = 0; i < n; i++) {
        graph[i][i] = 0;
    }
    int a, b;
    for (int i = 0; i < m; i++) {
        cin >> a >> b;
        cin >> graph[a - 1][b - 1];
    }
    FW();
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < n; j++) {
            if ((graph[i][j]!= INT_MAX) && (graph[j][i] != INT_MAX)) {
                graph[i][j] = 0;
                graph[j][i] = 0;
            }
        }
    }
    FW();
    int k;
    cin >> k;
    for (int i = 0; i < k; i++) {
        cin >> a >> b;
        if (graph[a - 1][b - 1] != INT_MAX) {
            cout << graph[a - 1][b - 1] << endl;
        }
        else{
            cout << -1 << endl;
        }
    }
    return 0;
}