Go: // Warshall–Floyd Algorithm

package main

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

var scanner = bufio.NewScanner(os.Stdin)

const INF = 0x7FFFFFFF

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
				} else {
					c_dist[i][j] = c_matrix[i][j]
				}
				if c_matrix[i][j] == 0{
					c_prev[i][j] = -1
				} else {
					c_prev[i][j] = i
				}
				if t_matrix[i][j] == 0{
					t_dist[i][j] = INF
				} else {
					t_dist[i][j] = t_matrix[i][j]
				}
				if t_matrix[i][j] == 0{
					t_prev[i][j] = -1
				} else {
					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]
					t_newlen := t_dist[i][k] + t_dist[k][j]
					if c_newlen < c_dist[i][j] {
						c_dist[i][j] = c_newlen
						c_prev[i][j] = c_prev[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 <cstdio>
using namespace std;
#define MAX 1001
#define INF 9999999

int sta_c[MAX+1][MAX+1],sta_t[MAX+1][MAX+1],cc[MAX],tt[MAX];
int n,m,a,b,c,t,k,p,q,r,mc,mt,nc,nt;
bool visit_c[MAX],visit_t[MAX];

int dijkstra(int s,int g,int ct){
    fill(cc,cc+MAX,INF); fill(visit_c,visit_c+MAX,false);
    fill(tt,tt+MAX,INF); fill(visit_t,visit_t+MAX,false);
    
    tt[s] = cc[s] = 0;
    while(true){
        mt = mc = INF;
        for(int i = 1 ; i <= m ; i++){
            if(cc[i] < mc && !visit_c[i]){
                mc = cc[i];
                nc = i;
            }
            if(tt[i] < mt && !visit_t[i]){
                mt = tt[i];
                nt = i;
            }
        }
        
        if(mc == INF && !ct) break;
        if(mt == INF && ct) break;
        
        visit_c[nc] = visit_t[nt] = true;
        
        for(int j = 1 ; j <= m ; j++){
            if(sta_c[nc][j]+cc[nc] < cc[j] && sta_c[nc][j] != INF){
                cc[j] = sta_c[nc][j]+cc[nc];
            }
            if(sta_t[nt][j]+tt[nt] < tt[j] && sta_t[nt][j] != INF){
                tt[j] = sta_t[nt][j]+tt[nt];
            }
        }
    }
    
    if(ct) return tt[g];
    return cc[g];
}

int main(){
    while(cin >> n >> m , n+m){
        fill(sta_c[0],sta_c[MAX],INF);
        fill(sta_t[0],sta_t[MAX],INF);
        while(n--){
            cin >> a >> b >> c >> t;
            
            sta_t[a][b] = sta_t[b][a] = t;
            sta_c[a][b] = sta_c[b][a] = c;
        }
        cin >> k;
        while(k--){
            cin >> p >> q >> r;
            cout << dijkstra(p,q,r) << endl;
        }
    }
    
    return 0;
}