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
			c_matrix[b-1][a-1] = c
			t_matrix[a-1][b-1] = t
			t_matrix[b-1][a-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>
#include <algorithm>
#include <set>
#include <queue>
#include <stack>
#include <string>
#include <map>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <cmath>

#define rep(i, n) for(int i = 0; i < n; i ++)
#define COUNT(i, n) for(int i = 1; i <= n; i ++)
#define ALL(T) T.begin(), T.end()
#define mp make_pair
#define pb push_back
#define ITER(c) __typeof((c).begin())
#define each(c, it) for(ITER(c) it = (c).begin(); it != (c).end(); it++)
#define X first
#define Y second

using namespace std;

typedef pair<int, int> pii;
typedef unsigned long long ull;
typedef vector<int> vi;
typedef vector<string> vs;

const int INF = 1 << 24;
const int N = 101;

int cost[N][N][2];
int d[N][N][2];
int n;
bool used[N];

void dijkstra(int, int);

int main(void){
    for(int m; cin >> m >> n, n;){
        rep(i, n) rep(j, n) rep(k, 2){
            cost[i][j][k] = INF;
            d[i][j][k] = -1;
        }
        while(m--){
            int a, b, c, t; cin >> a >> b >> c >> t;
            a--, b--;
            cost[a][b][0] = c;
            cost[b][a][0] = c;
            cost[a][b][1] = t;
            cost[b][a][1] = t;
        }
        int k; cin >> k;
        while(k--){
            int p, q, r; cin >> p >> q >> r;
            p--, q--;
            if(!~d[p][q][r]) dijkstra(p, r);
            cout << d[p][q][r] << endl;
        }
    }

    return 0;
}

void dijkstra(int s, int t){
    rep(i, n) d[s][i][t] = INF;
    rep(i, n) used[i] = false;
    d[s][s][t] = 0;

    while(1){
        int v = -1;
        rep(u, n) if(!used[u] && (!~v || d[s][u][t] < d[s][v][t])) v = u;

        if(!~v) break;
        used[v] = true;

        rep(u, n) d[s][u][t] = min(d[s][u][t], d[s][v][t] + cost[v][u][t]);
    }
}

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

int main(void)
{
	int n, m, a, b, c, t;
	int p, q, r;
	int cost[100][100], time[100][100];
	
	while (scanf("%d %d", &m, &n), n){
		for (int i = 0; i < 100; i++){
			for (int j = 0; j < 100; j++){
				if (i == j) cost[i][j] = time[i][j] = 0;
				else cost[i][j] = time[i][j] = 10000000;
			}
		}
		
		for (int i = 0; i < m; i++){
			cin >> a >> b >> c >> t;
			cost[a - 1][b - 1] = c;
			time[a - 1][b - 1] = t;
		}
		
		for (int k = 0; k < n; k++){
			for (int i = 0; i < n; i++){
				for (int j = 0; j < n; j++){
					cost[i][j] = min(cost[i][j], cost[i][k] + cost[k][j]);
					time[i][j] = min(time[i][j], time[i][k] + time[k][j]);
				}
			}
		}
		
		int k;
		cin >> k;
		for (int i = 0; i < k; i++){
			cin >> p >> q >> r;
			if (r == 0) cout << cost[p - 1][q - 1] << endl;
			else cout << time[p - 1][q - 1] << endl;
		}
	}
	
	return 0;
}

C++: #include<iostream>
#include<vector>
#include<queue>
#include<map>
#define pb push_back
#define INF 1000000000

using namespace std;
typedef pair<int,int> P;
int n;

struct edge{
	int to,cost;
	edge(int to,int cost):to(to),cost(cost){}
};
vector<vector<edge> > G1,G2;


int dijkstra1(int s,int t){
	priority_queue<P,vector<P> , greater<P> > que;
	vector<int> d(n,INF);
	d[s]=0;
	que.push(P(0,s));
	while(!que.empty()){
		P q=que.top();
		que.pop();
		int now=q.second,dist=q.first;
		if(now==t){
			return dist;
		}
		
		if(d[now]<dist)
			continue;
		
		for(int i=0;i<(int)G1[now].size();i++){
			if(G1[now][i].cost+dist<d[G1[now][i].to]){
				que.push(P(G1[now][i].cost+dist,G1[now][i].to));
				d[G1[now][i].to]=G1[now][i].cost+dist;
			}
		}
	}
	return -1;
	
}
int dijkstra2(int s,int t){
	priority_queue<P,vector<P> , greater<P> > que;
	vector<int> d(n,INF);
	d[s]=0;
	que.push(P(0,s));
	while(!que.empty()){
		P q=que.top();
		que.pop();
		int now=q.second,dist=q.first;
		if(now==t){
			return dist;
		}
		
		if(d[now]<dist)
			continue;
		
		for(int i=0;i<(int)G2[now].size();i++){
			if(G2[now][i].cost+dist<d[G2[now][i].to]){
				que.push(P(G2[now][i].cost+dist,G2[now][i].to));
				d[G2[now][i].to]=G2[now][i].cost+dist;
			}
		}
	}
	return -1;
}
int main(){
	int m;
	while(cin>>m>>n,n||m){
		
		G1.resize(n);
		G2.resize(n);
		for(int i=0;i<m;i++){
			int a,b,c,t;
			cin>>a>>b>>c>>t;a--;b--;
			G1[a].pb(edge(b,c));
			G1[b].pb(edge(a,c));
			G2[a].pb(edge(b,t));
			G2[b].pb(edge(a,t));
		}

		
		int k;
		cin>>k;
		for(int i=0;i<k;i++){
			int p,q,r;
			cin>>p>>q>>r;p--,q--;
			if(r==0){
				cout<<dijkstra1(p,q)<<endl;
			}else
				cout<<dijkstra2(p,q)<<endl;
			
			
		}
		
	}
	
	return 0;
}