Go: // Warshall–Floyd Algorithm

package main

import (
	"bufio"
	"fmt"
	"os"
	"strconv"
	"strings"
)

var scanner = bufio.NewScanner(os.Stdin)

const INF = 2000000000

func main() {
	for scanner.Scan() {
		buf := strings.Split(scanner.Text(), " ")
		n, _ := strconv.Atoi(buf[0])
		m, _ := strconv.Atoi(buf[1])
		if n == 0 && m == 0 {
			break
		}
		c_matrix := make([][]int, m)
		for i := range c_matrix {
			c_matrix[i] = make([]int, m)
		}
		t_matrix := make([][]int, m)
		for i := range t_matrix {
			t_matrix[i] = make([]int, m)
		}
		for i := 0; i < n; i++ {
			scanner.Scan()
			buf_ := strings.Split(scanner.Text(), " ")
			a, _ := strconv.Atoi(buf_[0])
			b, _ := strconv.Atoi(buf_[1])
			c, _ := strconv.Atoi(buf_[2])
			t, _ := strconv.Atoi(buf_[3])
			c_matrix[a-1][b-1] = c
			t_matrix[a-1][b-1] = t
		}
		c_dist := make([][]int, m)
		c_prev := make([][]int, m)
		t_dist := make([][]int, m)
		t_prev := make([][]int, m)
		for i := 0; i < m; i++ {
			c_dist[i] = make([]int, m)
			c_prev[i] = make([]int, m)
			t_dist[i] = make([]int, m)
			t_prev[i] = make([]int, m)
		}
		for i := 0; i < m; i++ {
			for j := 0; j < m; j++ {
				if c_matrix[i][j] == 0 {
					c_dist[i][j] = INF
					c_prev[i][j] = -1
				} else {
					c_dist[i][j] = c_matrix[i][j]
					c_prev[i][j] = i
				}
				if t_matrix[i][j] == 0 {
					t_dist[i][j] = INF
					t_prev[i][j] = -1
				} else {
					t_dist[i][j] = t_matrix[i][j]
					t_prev[i][j] = i
				}
			}
			c_dist[i][i] = 0
			t_dist[i][i] = 0
		}
		for k := 0; k < m; k++ {
			for i := 0; i < m; i++ {
				for j := 0; j < m; j++ {
					c_newlen := c_dist[i][k] + c_dist[k][j]
					if c_newlen < c_dist[i][j] {
						c_dist[i][j] = c_newlen
						c_prev[i][j] = c_prev[k][j]
					}
				}
			}
		}
		for k := 0; k < m; k++ {
			for i := 0; i < m; i++ {
				for j := 0; j < m; j++ {
					t_newlen := t_dist[i][k] + t_dist[k][j]
					if t_newlen < t_dist[i][j] {
						t_dist[i][j] = t_newlen
						t_prev[i][j] = t_prev[k][j]
					}

				}
			}
		}
		scanner.Scan()
		k, _ := strconv.Atoi(scanner.Text())
		for i := 0; i < k; i++ {
			scanner.Scan()
			buf_ := strings.Split(scanner.Text(), " ")
			p, _ := strconv.Atoi(buf_[0])
			q, _ := strconv.Atoi(buf_[1])
			r, _ := strconv.Atoi(buf_[2])
			switch r {
			case 0:
				fmt.Println(c_dist[p-1][q-1])
			case 1:
				fmt.Println(t_dist[p-1][q-1])
			}
		}
	}
}

C++: #include <iostream>
#include <vector>
using namespace std;

struct edge {
    int from, to, cost, time;
};

int main() {
    int n, m, a, b, v, u, k, p, q, r;
    while (cin >> n >> m, n || m) {
        vector<edge> edges;
        for (int i=0; i<n; ++i) {
            cin >> a >> b >> v >> u;
            edges.push_back((edge){ a, b, v, u });
        }
        cin >> k;
        for (int i=0; i<k; ++i) {
            cin >> p >> q >> r;
            int d[100];
            for (int i=0; i<100; ++i) d[i] = 1e8;
            d[p] = 0;
            for (int i=0; i<100; ++i) {
                for (int j=0; j<(int)edges.size(); ++j) {
                    edge &e = edges[j];
                    if (r == 0) {
                        d[e.to] = min(d[e.to], d[e.from] + e.cost);
                    } else {
                        d[e.to] = min(d[e.to], d[e.from] + e.time);
                    }
                }
            }
            cout << d[q] << endl;
        }
    }
    return 0;
}

C++: /* template.cpp(shinobu_menkoi) {{{ */
#include <bits/stdc++.h>
using namespace std;

// clang-format off
#define GET_MACRO(_1, _2, _3, _4, NAME, ...) NAME
#define rep(...) GET_MACRO(__VA_ARGS__, rep4, rep3, rep2, rep1)(__VA_ARGS__)
#define rep1(n) rep2(_, n)
#define rep2(i, n) rep3(i, 0, n)
#define rep3(i, a, n) rep4(i, a, n, 1)
#define rep4(i, a, n, s) for (lint i = (a); i < (lint)(n); i += (s))
#define rrep(...) GET_MACRO(__VA_ARGS__, rrep4, rrep3, rrep2, rrep1)(__VA_ARGS__)
#define rrep1(a) rrep2(_, a)
#define rrep2(i, a) rrep3(i, a, 0)
#define rrep3(i, a, n) rrep4(i, a, n, 1)
#define rrep4(i, a, n, s) for (lint i = (a); i >= (lint)(n); i -= (s))
#define each(i, ctn) for (auto &&i : (ctn))

#define pb push_back
#define eb emplace_back
#define mp make_pair
#define fi first
#define se second
#define all(v) begin(v), end(v)
#define debug(x) cerr << (x) << " (L:" << __LINE__ << ")" << '\n'
#define TEMP_T template <class T>
#define TEMP_TU template <class T, class U>

TEMP_T using vec = vector<T>;
TEMP_T using heap = priority_queue<T>;
TEMP_T using minheap = priority_queue<T, vec<T>, greater<T>>;
using lint = long long;
using ulint = unsigned long long;
using ld = long double;
using vi = vec<int>;
using vvi = vec<vi>;
using vvvi = vec<vvi>;
using pii = pair<int, int>;
using vs = vec<string>;

TEMP_TU ostream &operator<<(ostream &os, const pair<T, U> &p) { return os << p.fi << " " << p.se; }
TEMP_TU istream &operator>>(istream &is, pair<T, U> &p) { return is >> p.fi >> p.se; }

const int INF{1001001001};
const lint LINF{1001001001001001001ll};
const int MOD{(int)1e9 + 7};
const double EPS{1e-9};
const double PI{acos(-1)};
const int dx[]{0, 1, 0, -1, 1, -1, 1, -1}, dy[]{1, 0, -1, 0, 1, -1, -1, 1};

inline bool inside(int y, int x, int h, int w) { return y >= 0 && x >= 0 && y < h && x < w; }
TEMP_T inline bool chmin(T &a, const T &b) { if (a > b) a = b; return a > b; }
TEMP_T inline bool chmax(T &a, const T &b) { if (a < b) a = b; return a < b; }
TEMP_T inline void print(const T &x) { cout << x << '\n'; }
TEMP_T inline void print(const vec<T> &v, string d = "\n") { rep(i, v.size()) cout << v[i] << (i == (lint)v.size() - 1 ? "\n" : d); }
template <class T = int> inline T in() { T x; cin >> x; return x; }
template <class T = string> vec<T> split(const string &s, char d = ',') {
  vec<T> v; stringstream ss(s); for (string b; getline(ss, b, d); ) {
    stringstream conv(b); T t; conv >> t; v.eb(t); } return v;
}
struct pre_ { pre_() { cin.tie(nullptr); ios::sync_with_stdio(false); cout << fixed << setprecision(12); } } pre__;
// clang-format on
/* }}} */

void warshall_floyd(vvi& d) {
  int N = d[0].size();

  rep(k, N) rep(i, N) rep(j, N) {
    chmin(d[i][j], d[i][k] + d[k][j]);
  }
}

signed main() {
  int n, m;
  while (cin >> n >> m, n || m) {
    vvi d1(m, vi(m, INF)), d2(m, vi(m, INF));
    rep(i, n) {
      int a, b, cost, time;
      cin >> a >> b >> cost >> time;
      a--; b--;
      d1[a][b] = d1[b][a] = cost;
      d2[a][b] = d2[b][a] = time;
    }
    warshall_floyd(d1);
    warshall_floyd(d2);
    int k;
    cin >> k;

    rep(i, k) {
      int a, b, kind;
      cin >> a >> b >> kind;
      a--; b--;
      print(kind ? d2[a][b] : d1[a][b]);
    }
  }
}