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]
					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<stdio.h>
#define INF 100001
int e1[100][100],e2[100][100];
int d[100];
bool used[100];
int m,n;
int p,q,r;
int k;
int i,j;
int a,b,t,c;
int v;
int mc,mt;

int min(int a,int b){
	if(a<=b)return a;
	else return b;
}

void solve(int s,int mo){
	for(j=0;j<m;j++){
		used[j]=false;
		d[j]=INF;
	}
	d[s]=0;
	while(true){
		v=-1;
		for(int u=0;u<m;u++)if(!used[u]&&(v==-1||d[u]<d[v]))v=u;
		if(v==-1)break;
		used[v]=true;
		for(int u=0;u<m;u++){
			if(mo==0)d[u]=min(d[u],d[v]+e1[v][u]);
			else d[u]=min(d[u],d[v]+e2[v][u]);
		}
	}
}


int main(){
	while(1){
		scanf("%d %d",&n,&m);
		if(n==0&&m==0)break;
		mt=INF;
		mc=INF;
		for(i=0;i<m;i++)for(j=0;j<m;j++){
			e1[i][j]=INF;
			e2[i][j]=INF;
		}
		for(i=0;i<n;i++){
			scanf("%d %d %d %d",&a,&b,&c,&t);
			e1[a-1][b-1]=c;
			e1[b-1][a-1]=c;
			e2[a-1][b-1]=t;
			e2[b-1][a-1]=t;
		}
		scanf("%d",&k);
		for(i=0;i<k;i++){
			scanf("%d %d %d",&p,&q,&r);
			solve(p-1,r);
			if(r==0)mc=min(mc,d[q-1]);
			else mt=min(mt,d[q-1]);
		}
		printf("%d\n%d\n",mc,mt);
	}
}

C++: #include<iostream>
#include<algorithm>
#define MAX 1000000
using namespace std;
int main(){
	int n, m, a, b, cost, ti, k, p, q, r, point = 0;
	int cost_[101][101], time_[101][101], k_[601];
	for (int i = 0; i < 101; i++){
		for (int l = 0; l < 101; l++){
			cost_[i][l] = MAX;
			time_[i][l] = MAX;
		}
	}
	cin >> n >> m;
	while (n != 0 && m != 0){
		for (int i = 0; i < n; i++){
			cin >> a >> b >> cost >> ti;
			cost_[a][b] = cost;
			time_[a][b] = ti;
		}
		cin >> k;
		for (int i = 0; i < k; i++){
			cin >> p >> q >> r;
			k_[point] = p;
			k_[point + 1] = q;
			k_[point + 2] = r;
			point += 3;
		}point = 0;
		for (int i = 1; i <= m; i++){
			for (int j = 1; j <= m; j++){
				for (int o = 1; o <= m; o++){
					if (cost_[j][i] != MAX && cost_[i][o] != MAX &&
						time_[j][i] != MAX && time_[i][o] != MAX){
						cost_[j][o] = min(cost_[j][o], cost_[j][i] + cost_[i][o]);
						time_[j][o] = min(time_[j][o], time_[j][i] + time_[i][o]);
					}
				}
			}
		}
		for (int i = 0; i < k; i++){
			if (k_[point + 2] == 0){
				cout << cost_[k_[point]][k_[point + 1]] << endl;
			}
			else cout << time_[k_[point]][k_[point + 1]] << endl;
			point += 3;
		}point = 0;
		cin >> n >> m;
	}
	return 0;
}

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

#define FOR(i,k,n) for(int i = (k); i < (n); i++)
#define REP(i,n) FOR(i,0,n)
#define INF 114514810
#define ll long long

int main()
{

	int cost[101][101];
	int time_[101][101];

	while (1)
	{
		int n, m;
		cin >> n >> m; if (n == 0 && m == 0) break;
		REP(i, 101)REP(j, 101)
		{
			if (i == j)
			{
				cost[i][j] = 0;
				time_[i][j] = 0;
			}
			else
			{
				cost[i][j] = INF;
				time_[i][j] = INF;
			}
		}

		REP(i, 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;
		}

		REP(i, m)REP(j, m)REP(k, m)
		{
			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;
		REP(i, k)
		{
			int p, q, r;
			cin >> p >> q >> r;
			p--; q--;
			if (r == 0) cout << cost[p][q] << endl;
			else cout << time_[p][q] << endl;
		}
	}
	return 0;
}