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 "bipartite-graph.hpp"
//#include <vector>
//using namespace std;
//int main(){
//	vector<vector<int> > G(4);
//	cout << bipartite_graph(G) << endl;
//}

// AOJ0200
#include <iostream>
#include <vector>
using namespace std;

struct edge {
    edge(){}
    edge(int to, int from, int cost, int time): to(to), from(from), cost(cost), time(time) {}
    int to, from, cost, time;
};

const int INF = 100000000;

int d[101];
edge es[2000];
int n,m;

// 頂点sから各頂点への最短経路を求める
void bellman_ford(int s, bool r){
    for (int i = 0; i < m; ++i) d[i]=INF;
    d[s]=0;
    while(1){
        bool update=false;
        for (int i = 0; i < n*2; ++i) {
            edge e=es[i];
            int cost;
            if(r) cost=e.time;
            else cost=e.cost;
            if(d[e.from]!=INF && d[e.to]>d[e.from]+cost){
                d[e.to]=d[e.from]+cost;
                update=true;
            }
        }
        if(!update) break;
    }
}

int main(){
    while(cin >> n >> m,n+m){
        for (int i = 0; i < n; ++i) {
            int to,from,cost,time;
            cin >> to>>from>>cost>>time;
            es[i]=edge(to-1,from-1,cost,time);
            es[n+i]=edge(from-1,to-1,cost,time);
        }
        int k; cin>>k;
        for (int i = 0; i < k; ++i) {
            int p,q,r;
            cin>>p>>q>>r;
            bellman_ford(p-1,r);
            cout<<d[q-1]<<endl;
        }
    }
}

C++: #include<iostream>
#include<string>
#include<algorithm>
#include<list>
#include<set>
#include<map>
#include<queue>
#include<stack>
#include<numeric>
#include<vector>
#include<cstdio>
#include<climits>
#include<cfloat>
#include<cstring>
#define foreach(t,p,tit) for(t::iterator tit=p.begin();tit!=p.end();++tit)
#define rforeach(t,p) for(t::reverse_iterator it=p.rbegin();it!=p.rend();++it)
#define all(p) p.begin(),p.end()
#define rep(i,n) for(int i=0;i<n;i++)
using namespace std;
int costs[1010][1010];
int times[1010][1010];
int d[1010];
#define INF 10000
struct E
{
    int a,b,c;
    E(){};
    E(int a,int b,int c):a(a),b(b),c(c){};
};
#define MONEY 0
#define EKI 1

int main()
{
    int n,m;
    while(cin>>n>>m)
    {
        if(n==0&&m==0)break;
        memset(costs,INF,sizeof(costs));
        memset(times,INF,sizeof(times));
        vector<E> cs;
        vector<E> ts;
        int a,b,c,t;
        rep(i,n)
        {
            cin>>a>>b>>c>>t;
            costs[a][b] = c; costs[b][a] = c;
            times[a][b] = t; times[b][a] = t;
            cs.push_back(E(a,b,c));
            cs.push_back(E(b,a,c));
            ts.push_back(E(a,b,t));
            ts.push_back(E(b,a,t));
        }
        rep(i,m)
        {
            costs[i][i] = 0;
            times[i][i] = 0;
        }
        int k,p,q,r;
        cin>>k;
        rep(i,k)
        {
            memset(d,INF,sizeof(d));
            cin >> p >> q >> r;
            d[p] = 0;
            if(r==MONEY)
            {
                //rep(j,n*2){if(cs[j].a == p) d[cs[j].b] = cs[j].c;}
                while(true)
                {
                    bool update = false;
                    rep(j,n*2)
                    {
                        //cout <<"edge"<< j<<cs[j].a<<"to"<<cs[j].b << endl;

                        if( (d[ cs[j].a] != INF) && d[cs[j].b] > d[cs[j].a] + cs[j].c)
                        {
                            d[cs[j].b] = d[ cs[j].a] + cs[j].c;
                            update = true;
                            //cout << "updated" <<d[cs[j].b] <<endl;
                        }
                    }
                    if(!update)break;
                }
                cout << d[q]<<endl;
            }
            else
            {
                //rep(j,n*2){if(ts[j].a == p) d[ts[j].b] = ts[j].c;}
                while(true)
                {
                    bool update = false;
                    rep(j,n*2)
                    {
                        if(d[ ts[j].a] != INF && d[ts[j].b] > d[ts[j].a] + ts[j].c)
                        {
                            d[ts[j].b] = d[ ts[j].a] + ts[j].c;
                            update = true;
                        }
                    }
                    if(!update)break;
                }
                cout << d[q]<<endl;
            }
        }
    }

    return 0;
}