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<bits/stdc++.h>
#define ll long long int
#define FOR(i,a,b) for(ll i=(ll)(a);i<(ll)(b);i++)
#define REP(i,n) FOR(i,0,n)
#define REP1(i,n) FOR(i,1,n)
#define MIN(a, b) ((a)<(b)?(a):(b))
#define MAX(a, b) ((a)<(b)?(a):(b))
#define INF 10e6
using namespace std;
 /*temp*/

int main(){
    int n, m, l;
    while(cin>>m>>n,n){
        int cost[n][n],time[n][n];
        // set table
        REP(i,n){
            REP(j,n){
                cost[i][j]=time[i][j]=INF;
            }
            cost[i][i]=time[i][i]=0;
        }
        // read
        REP(i,n){
            int a,b,c,t;
            a--;
            b--;
            cost[a][b]=cost[b][a]=c;
            time[a][b]=time[b][a]=t;
        }
        // Warshall???Floyd Algorithm
        REP(a,n){
            REP(b,a+1){
                REP(k,n){
                    cost[a][b]=cost[b][a]=MIN(cost[a][b],cost[a][k]+cost[k][b]);
                    time[a][b]=time[b][a]=MIN(time[a][b],time[a][k]+time[k][b]);
                }
            }
        }
        // 
        int q;
        cin>>q;
        REP(i,q){
            int s,d,type;
            cin>>s>>d>>type;
            s--;
            d--;
            cout<<type==0?cost[s][d]:time[s][d]<<'\n';
        }
    }
    return 0;
}

C++: #include <iostream>
#include <stdlib.h>
#define inf 99999

using namespace std;

bool check(int *label, int n)
{
	for(int i = 1; i <= n; i++){
		if(label[i] == 0){
			return true;
		}
	}
	
	return false;
}

void dij(int **a, int n, int s, int t)
{
	int *label, current=s, num=1, next, *cost, min;
	
	cost = (int *)calloc(n+1, sizeof(int));
	label = (int *)calloc(n+1, sizeof(int));
	
	for(int i = 1; i <= n; i++){
		cost[i] = a[current][i];
	}
	label[current] = num++;
	
	while(check(label, n)){
		min = inf;
		for(int i = 1; i <= n; i++){
			if(min >= cost[i] && label[i] == 0){
				min = cost[i];
				next = i;
			}
		}
		label[next] = num++;
		for(int i = 1; i <= n; i++){
			if(label[i] == 0 && cost[i] > (a[next][i]+cost[next])){
				cost[i] = a[next][i] + cost[next];
			}
		}
		current = next;
	}
	cout << cost[t] << endl;
	
	free(cost);
	free(label);
	
	return ;
}

int main(int argc, char **argv)
{
	int **t, **c, n, m, a, b, p, q;
	
	while(1){
		cin >> n >> m;
		if(n == 0 && m == 0){
			break;
		}
		
		t = (int **)calloc(m+1, sizeof(int));
		c = (int **)calloc(m+1, sizeof(int));
		for(int i = 0; i <= m; i++){
			t[i] = (int *)calloc(m+1, sizeof(int));
			c[i] = (int *)calloc(m+1, sizeof(int));
		}
		
		for(int i = 0; i < n; i++){
			cin >> a >> b >> p >> q;
			c[a][b] = c[b][a] = p;
			t[a][b] = t[b][a] = q;
		}
		for(int i = 1; i <= m; i++){
			for(int j = 1; j <= m; j++){
				if(i != j && c[i][j] == 0){
					c[i][j] = inf;
				}
				if(i != j && t[i][j] == 0){
					t[i][j] = inf;
				}
			}
		}
		cin >> n;
		for(int i = 0; i < n; i++){
			cin >> a >> b >> p;
			if(p == 0){
				dij(c, m, a, b);
			} else {
				dij(t, m, a, b);
			}
		}
		
		for(int i = 0; i <= m; i++){
			free(t[i]);
			free(c[i]);
		}
		free(t);
		free(c);
	}
	
	return 0;
}

C++: #include <iostream>
#include <iomanip>
#include <sstream>
#include <stdio.h>
#include <vector>
#include <stack>
#include <queue>
#include <algorithm>
#include <math.h>
#include <utility>
#include <string>
#include <ctype.h>
#include <cstring>
#include <cstdio>
#include <sstream>
#include <functional>

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
//#define scanf scanf_s

int n, m, a, b, c, t, p, q, r;
int cost[101][101];
int time_[101][101];

int main()
{

	while (1)
	{
		cin >> n >> m; if (n == 0 && m == 0) return 0;
		REP(i, n)REP(j, n)
		{
			if (i == j)
			{
				cost[i][j] = 0;
				time_[i][j] = 0;
			}
			else
			{
				cost[i][j] = INF;
				time_[i][j] = INF;
			}
		}
		
		REP(i, n)
		{
			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 que;
		cin >> que;
		REP(i, que)
		{
			cin >> p >> q >> r;
			p--; q--;
			if (r == 0) cout << cost[p][q] << endl;
			else cout << time_[p][q] << endl;

		}
	}
}