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 <algorithm>
using namespace std;
const int INF = 1000000;
int cost[301][301],time[301][301];
void time_WF(int m){
	for(int k = 0;k <= m;++k){
		for(int i = 0;i <= m;++i){
			for(int j = 0;j <= m;++j){
				time[i][j] = min(time[i][j],time[i][k] + time[k][j]);
			}
		}
	}
	return;
}
void cost_WF(int m){
	for(int k = 0;k <= m;++k){
		for(int i = 0;i <= m;++i){
			for(int j = 0;j <= m;++j){
				cost[i][j] = min(cost[i][j],cost[i][k] + cost[k][j]);
			}
		}
	}
	return;
}
int main(){
	int n,m;
	while(cin >> n >> m,n || m){
		int a,b,icost,itime,c,r;
		for(int i = 0;i <= m;++i){
			for(int j = 0;j <= m;++j){
				if(i == j) {
					cost[i][i] = 0;
					time[i][i] = 0;
				}
				else {
					cost[i][j] = cost[j][i] = INF;
					time[i][j] = time[j][i] = INF;
				}
			}
		}
		for(int i = 0;i < n;++i){
			cin >> a >> b >> icost >> itime;
			cost[a][b] = cost[b][a] = icost;
			time[a][b] = time[b][a] = itime;
		}
		cin >> c;
		for(int i = 0;i < c;++i){
			cin >> a >> b >> r;
			if(r == 1){
				time_WF(m);
				cout << time[a][b] << endl;
			}
			else {
				cost_WF(m);
				cout << cost[a][b] << endl;
			}
		}
	}
	return 0;
}

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

template <typename T>
struct Edge { int src, dst; T cost;
    Edge(int dst, T cost) : src(-1), dst(dst), cost(cost) { }
    Edge(int src, int dst, T cost) : src(src), dst(dst), cost(cost) { }
};
template <typename T> using Edges = vector<Edge<T>>;
template <typename T> using WeightedGraph = vector<Edges<T>>;
template <typename T> using Matrix = vector<vector<T>>;

template <typename T>
void warshall_floyd(Matrix<T> &g) {
    const T INF = numeric_limits<T>::max();
    for (int k = 0; k < g.size(); k++) {
        for (int i = 0; i < g.size(); i++) if (g[i][k] != INF) {
            for (int j = 0; j < g.size(); j++) if (g[k][j] != INF) {
                g[i][j] = min(g[i][j], g[i][k] + g[k][j]);
            }
        }
    }
}

int main() {
    int n, m;
    const auto INF = numeric_limits<int>::max();
    while (cin >> n >> m, n) {
        Matrix<int> cost(m, vector<int>(m, INF));
        Matrix<int> time(m, vector<int>(m, INF));
        for (int i = 0; i < m; i++) cost[i][i] = 0, time[i][i] = 0;
        while (n--) {
            int a, b, c, t; cin >> a >> b >> c >> t; a--, b--;
            cost[a][b] = cost[b][a] = c;
            time[a][b] = time[b][a] = t;
        }
        warshall_floyd(cost);
        warshall_floyd(time);
        int k; cin >> k;
        while (k--) {
            int p, q, r; cin >> p >> q >> r; p--, q--;
            cout << (r == 0 ? cost[p][q] : time[p][q]) << endl;
        }
    }
    return 0;
}

C++: //AOJ 0200
//菴ソ縺?婿繧ゅｏ縺九ｉ縺ェ縺?¥縺帙↓include縺励∪縺上ｋ莠コ髢薙?繧ッ繧コ
#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<algorithm>
#include<cmath>
#include<stack>
#include<queue>
#include<vector>
#include<list>
#include<deque>
using namespace std;
#define INF 1 << 20
#define MAX_B 101

int a, b, i, j, k, money[MAX_B][MAX_B], time[MAX_B][MAX_B], n, m, c, d;
bool judge;
stack<int> left, right;


int main(){
  while(1){
    scanf("%d %d", &n, &m);
    if(n == 0 && m == 0) return 0;
    for(i = 1; i <= m; i++){
      for(j = 1; j <= m; j++){
	money[i][j] = INF;
	time[i][j] = INF;
      }
    }
    for(i = 1; i <= m; i++){
      money[i][i] = 0;
      time[i][i] = 0;
    }
    for(i = 0; i < n; i++){
      scanf("%d %d %d %d", &a, &b, &c, &d);
      money[a][b] = c;
      money[b][a] = c;
      time[a][b] = d;
      time[b][a] = d;
    }
    scanf("%d", &a);
    for(i = 1; i <= m; i++){
      for(j = 1; j <= m; j++){
	for(k = 1; k <= m; k++){
	  if(money[j][k] > money[j][i] + money[i][k]){
	    money[j][k] = money[j][i] + money[i][k];
	    money[k][j] = money[j][i] + money[i][k];
	  }
	  if(time[j][k] > time[j][i] + time[i][k]){
	    time[j][k] = time[j][i] + time[i][k];
	    time[k][j] = time[j][i] + time[i][k];
	  }
	}
      }
    }
    for(i = 0; i < a; i++){
      scanf("%d %d %d", &b, &c, &d);
      if(d == 1)
	printf("%d\n", time[b][c]);
      if(d == 0)
	printf("%d\n", money[b][c]);
    }
  }
  return 0;
}