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++: import sys
import heapq as h

inf = sys.maxsize

# おまじない
class heapq:
    def __init__(self):
        self.q = []

    def push(self,v):
        h.heappush(self.q, v)
    
    def pop(self):
        return h.heappop(self.q)

    def is_empty(self):
        return len(self.q) == 0

# 入力:graphと始点s
# 出力:始点sから各頂点tへの距離dist
def shortestPath0(graph, s):
    n = len(graph)

    dist    = [inf for _ in range(n)]
    visited = [False for _ in range(n)]
    dist[s] = 0

    while True:
        idx, u  = -1, inf
        for i in range(n):
            if not visited[i] and dist[i] < u:
                idx = i
                u = dist[i]
        
        if u == inf: break
        
        visited[idx] = True

        for (next, w) in graph[idx]:
            newdist = w + dist[idx]
            if newdist < dist[next]:
                dist[next] = newdist
    return dist

def shortestPath1(graph, s):
    n = len(graph)

    dist    = [inf for _ in range(n)]
    visited = [False for _ in range(n)]
    
    q = heapq()
    q.push((0, s))

    while not q.is_empty():
        (cur_dist, v) = q.pop()

        if visited[v] or dist[v] <= cur_dist:
            continue

        dist[v] = cur_dist
        visited[v] = True

        for next, w in graph[v]:
            if not visited[next] and dist[v] + w < dist[next]:
                q.push((dist[v] + w, next))

    return dist

def main():
    while True:
        n, m = map(int, input().split())
        if n == 0 and m == 0:
            break
        # 隣接リスト
        tgraph = [[] for _ in range(m)]
        cgraph = [[] for _ in range(m)]
        
        for i in range(n):
            a, b, cost, time = map(int, input().split())
            a -= 1
            b -= 1
            cgraph[a].append((b, cost))
            cgraph[b].append((b, cost))
            tgraph[a].append((b, time))
            tgraph[b].append((b, time))
            
        c_dist = [shortestPath1(cgraph, s) for s in range(m)]
        t_dist = [shortestPath1(tgraph, s) for s in range(m)]

        k = int(input())
        for i in range(k):
            p, q, r = map(int, input().split())
            p-=1
            q-=1
            if r == 0:
                print(c_dist[p][q])
            else:
                print(t_dist[p][q])
main()

C++: #include<stdio.h>
#include<stdlib.h>
#include<math.h>
#include<iostream>
#include<string>
#include<algorithm>
#include<queue>
#include<utility>

using namespace std;

int n,m;

long long gc[110][110];
long long gt[110][110];

void warshallfloyd()
{
	for (int k = 0; k < m; k++)
	{
		for (int i = 0; i < m; i++)
		{
			for (int j = 0; j < m; j++)
			{
				gc[i][j] = min(gc[i][j], gc[i][k] + gc[k][j]);
				gt[i][j] = min(gt[i][j], gt[i][k] + gt[k][j]);
			}
		}
	}
}

int main(void)
{
	while (cin >> n >> m, n || m)
	{

		for (int i = 0; i < n; i++)
		{
			for (int j = 0; j < n; j++)
			{
				gc[i][j] = 9999999;
				gt[i][j] = 9999999;
			}
		}

		for (int i = 0; i < n; i++)
		{
			int a, b, c, t;

			cin >> a >> b >> c >> t;

			a--; b--;

			gc[a][b] = gc[b][a] = c;
			gt[a][b] = gt[b][a] = t;
		}

		warshallfloyd();

		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 << gc[p][q] << endl;
			}
			else
			{
				cout << gt[p][q] << endl;
			}
		}
	}

	

	return 0;
}

C++: #include <cstdio>
#include <cstdlib>
#include <cmath>
#include <climits>
#include <cfloat>
#include <map>
#include <utility>
#include <ctime>
#include <set>
#include <iostream>
#include <memory>
#include <string>
#include <cstring>
#include <vector>
#include <algorithm>
#include <functional>
#include <fstream>
#include <sstream>
#include <complex>
#include <stack>
#include <queue>
#include <cstring>
#include <numeric>
#include <cassert>
using namespace std;
#define rep(i, n) for (int(i) = 0; (i) < (n); (i)++)
class Timer
{
  private:
    double time_limit;
    //unsigned long long int cycle_per_sec = 2500000000; // Topcoder
    unsigned long long int cycle_per_sec = 2777777777; // AtCoder
    unsigned long long int beginCycle;
    unsigned long long int getCycle()
    {
        unsigned int low, high;
        __asm__ volatile("rdtsc"
                         : "=a"(low), "=d"(high));
        return ((unsigned long long int)low) | ((unsigned long long int)high << 32);
    }

  public:
    Timer(double time_limit) : time_limit(time_limit)
    {
        beginCycle = getCycle();
    }

    double elapsedTime()
    {

        return (double)(getCycle() - beginCycle) / cycle_per_sec;
    }
    bool isTLE()
    {
        return elapsedTime() >= time_limit;
    }
};

Timer gtimer(2.85);

int main()
{
    int m, n;
    while (cin >> m >> n && m)
    {
        int wf[2][110][110] = {};
        rep(i, 2) rep(j, 110) rep(k, 110)
            wf[i][j][k] = j == k ? 0 : 1e9;

        for (int i = 0; i < m; i++)
        {
            int a, b, c, t;
            cin >> a >> b >> c >> t;
            --a, --b;
            wf[0][a][b] = min(wf[0][a][b], c);
            wf[1][a][b] = min(wf[1][a][b], t);
        }
        rep(i, 2)
        {
            rep(j, 110) rep(k, 110) rep(l, 110)
            {
                wf[i][k][l] = min(wf[i][k][j] + wf[i][j][l], wf[i][k][l]);
            }
        }
        int Q;
        cin >> Q;
        while (Q--)
        {
            int a, b, c;
            cin >> a >> b >> c;
            --a, --b;
            cout << wf[c][a][b] << endl;
        }
    }
    std::cout.flush();
    return 0;
}