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 <string>
#include <vector>
#include <algorithm>
#include <cmath>
#include <cstdio>
#include <functional>
#include <numeric>
#include <stack>
#include <queue>
#include <map>
#include <set>
#include <utility>
#include <sstream>
#include <complex>

using namespace std;

#define FOR(i,a,b) for(long long i=(a);i<(b);i++)
#define REP(i,N) for(long long i=0;i<(N);i++)
#define ALL(s) (s).begin(),(s).end()
#define fi first
#define se second

#define PI acos(-1.0)
#define INF 1000000007
#define EPS 1e-10

typedef long long ll;
typedef pair<ll, ll> P;
typedef pair<double, double> PD;
typedef pair<string, ll> PS;
typedef vector<ll> V;
typedef pair<P, char> PC;


int dpt[111][111];
int dpc[111][111];
int n, m, a, b, cost, time, k, p, q, r;

int main(){
	while (cin >> n >> m&&n + m){
		REP(i, 111)REP(j, 111){
			if (i == j){
				dpt[i][j] = 0;
				dpc[i][j] = 0;
			}
			else{
				dpt[i][j] = INF;
				dpc[i][j] = INF;
			}
		}
		REP(i, n){
			cin >> a >> b >> cost >> time;
			dpt[a][b] = time;
			dpt[b][a] = time;
			dpc[a][b] = cost;
			dpc[b][a] = cost;
		}
		FOR(i, 1, m + 1){
			FOR(j, 1, m + 1){
				FOR(k, 1, m + 1){
					dpt[i][j] = min(dpt[i][j], dpt[i][k] + dpt[k][j]);
					dpc[i][j] = min(dpc[i][j], dpc[i][k] + dpc[k][j]);
				}
			}
		}
		cin >> k;
		REP(i, k){
			cin >> p >> q >> r;
			if (r == 0)cout << dpc[p][q] << endl;
			else cout << dpt[p][q] << endl;
		}
	}
}

C++: #include<iostream>

#define INF 100000;
using namespace std;


int main(){
  int n,m;
  while(1){
    cin>>n>>m;
    if(n==0&&m==0){break;}
    int s_tim[m][m];
    int c_money[m][m];
    int a,b,cost,tim;

    for(int i=0;i<m;i++){
      for(int j=0;j<m;j++){
        s_tim[i][j]=INF;
        c_money[i][j]=INF;
      }
    }
    for(int i=0;i<m;i++){
      s_tim[i][i]=0;
      c_money[i][i]=0;
    }
    for(int i=0;i<n;i++){
      cin>>a>>b>>cost>>tim;
      s_tim[a-1][b-1]=tim;s_tim[b-1][a-1]=tim;
      c_money[a-1][b-1]=cost;c_money[b-1][a-1]=cost;
    }

    for(int k=0;k<m;k++){
      for(int i=0;i<m;i++){
        for(int j=0;j<m;j++){
          if(s_tim[i][j]>s_tim[i][k]+s_tim[k][j]){
            s_tim[i][j]=s_tim[i][k]+s_tim[k][j];
          }
          if(c_money[i][j]>c_money[i][k]+c_money[k][j]){
            c_money[i][j]=c_money[i][k]+c_money[k][j];
          }
        }
      }
    }

    int contacts,p,q,r;
    cin>>contacts;

    for(int i=0;i<contacts;i++){
      cin>>p>>q>>r;
      if(r){cout<<s_tim[p-1][q-1];}
      else{ cout<<c_money[p-1][q-1];}
      cout<<endl;
    }
  }
}

C++: #include <iostream>
#include <cstring>
#include <algorithm>
#include <vector>
using namespace std;
#define rep(i, n) for(int i=0;i<(int)n;++i)

const int INF = 100000000;

unsigned int stat[110][110];
unsigned int stac[110][110];
int N, M, K;

int main() {
	while(cin >> N >> M && N && M) {
		for(int i = 0; i <= 100; i++) {
			for(int j = 0; j <= 100; j++) {
				stat[i][j] = INF;
				stac[i][j] = INF;
			}
		}
		rep(i, N) {
			int a, b, time, cost;
			cin >> a >> b >> cost >> time;
			stat[a][b] = time;
			stat[b][a] = time;
			stac[a][b] = stac[b][a] = cost;
		}
		for (int k = 1; k <= M; k++)
			for (int i = 1; i <= M; i++)
				for (int j = 1; j <= M; j++) {
					stat[i][j] = min(stat[i][j], stat[i][k] + stat[k][j]);
					stac[i][j] = min(stac[i][j], stac[i][k] + stac[k][j]);
				}

		cin >> K;
		rep(i, K) {
			int p, q, r;
			cin >> p >> q >> r;
			if(r == 0) {
				cout << stac[p][q] << endl;
			} else {
				cout << stat[p][q] << endl;
			}
		}
	}
	return 0;
}