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 <vector>
#include <array>
#include <algorithm>
#include <iterator>
using namespace std;

struct AboutTo;

class Node{
public:
	int aa;
	int Lowest;
	bool IsSelected;
	vector<AboutTo> ToCollection;
	Node(){
		Lowest = 2147483647;
		IsSelected = false;
	}
	void Reset(){
		Lowest = 2147483647;
		IsSelected = false;
	}
};
struct AboutTo{
	Node* To;
	int Cost;
	int Time;
};

int GetShortest(const int a,const Node GoalNode, vector<Node> &aNodeCol, const int IsTime){
	aNodeCol[a].IsSelected = true;
	int TempMin = 2147483647;
	int aNode;
	for (auto i = aNodeCol.begin(); i != aNodeCol.end(); ++i){
		if ((*i).IsSelected){
			for (auto j = (*i).ToCollection.begin(); j != (*i).ToCollection.end(); ++j){
				if (!(*((*j).To)).IsSelected){
					if (IsTime){
						if (TempMin>(*i).Lowest + (*j).Time){
							TempMin = (*i).Lowest + (*j).Time;
							aNode = (*((*j).To)).aa;
						}
					}
					else{
						if (TempMin>(*i).Lowest + (*j).Cost){
							TempMin = (*i).Lowest + (*j).Cost;
							aNode = (*((*j).To)).aa;
						}
					}
				}
			}
		}
	}
	aNodeCol[aNode].Lowest = TempMin;
	if (aNode != GoalNode.aa){	
		return GetShortest(aNode, GoalNode, aNodeCol, IsTime);
	}
	return TempMin;
}

int main(){
	while (true){
	int n, m;
	cin >> n >> m;
	if (n == 0 && m == 0)break;
		static vector<Node> NodeCollection;
		for (int i = 0; i < m; ++i){
			Node aNode;
			aNode.aa = i;
			NodeCollection.push_back(aNode);
		}
		for (int i = 0; i < n; ++i){
			int a, b, cost, time;
			cin >> a >> b >> cost >> time;
			NodeCollection[a - 1].ToCollection.push_back({ &NodeCollection[b - 1], cost, time });
			NodeCollection[b - 1].ToCollection.push_back({ &NodeCollection[a - 1], cost, time });
		}
		/*
		12 9
		1 2 5 5
		2 3 4 4
		3 6 3 10
		6 9 1 1
		9 8 7 6
		8 7 4 3
		7 4 2 1
		4 1 10 14
		2 5 7 8
		5 8 9 10
		4 5 9 9
		5 6 10 1
		*/
		int k;
		cin >> k;
		for (int i = 0; i < k; ++i){
			int p, q, r;
			cin >> p >> q >> r;
			NodeCollection[p - 1].Lowest = 0;
			if (p == q){cout << 0 << endl;
			}
			else{
				cout << GetShortest(p - 1, NodeCollection[q - 1], NodeCollection, r) << endl;
			}
			for (auto i = NodeCollection.begin(); i != NodeCollection.end(); ++i){
				(*i).Reset();
			}
		}
	}
	return 0;
}

C++: #include <stdio.h>
#include <vector>

using namespace std;

class Edge{
public:
	int from,to,cost,time;
	void swap(){
		int self = from;
		from = to;
		to = self;
	}
	int getvalue(int r){
		if(r == 0){
			return cost;
		}else{
			return time;
		}
	}
};

vector<Edge> edge;
int n,m;

int solve(const int p,const int q,const int r);

int main(){
	edge.clear();
	scanf("%d %d",&n,&m);
	for(int i=0;i<n;i++){
		Edge ed;
		scanf("%d %d %d %d",&ed.from,&ed.to,&ed.cost,&ed.time);
		edge.push_back(ed);
		ed.swap();
		edge.push_back(ed);
	}
	
	int k;
	scanf("%d",&k);
	for(int i=0;i<k;i++){
		int p,q,r;
		scanf("%d %d %d",&p,&q,&r);
		printf("%d\n",solve(p,q,r));
	}
}

int solve(const int p,const int q,const int r){
	const int INF = 2147483647;
	int a[100];
	for(int i=0;i<100;i++){
		a[i] = INF;
	}
	a[p] = 0;
	bool update;
	while(true){
		update = false;
		vector<Edge>::iterator it = edge.begin();
		while(it != edge.end()){
			if(a[(*it).from] != INF && a[(*it).to] > a[(*it).from] + (*it).getvalue(r)){
				a[(*it).to] = a[(*it).from] + (*it).getvalue(r);
				update = true;
			}
			it++;
		}
		if(!update){
			break;
		}
	}
	
	int ans = a[q];
	return a[q];
}

C++: #define _CRT_SECURE_NO_WARNINGS
#include <iostream>
#include <vector>
#include <set>
#include <map>
#include <sstream>
#include <string>
#include <cstdio>
#include <stack>
#include <queue>
#include <algorithm>
#include <numeric>
#include <functional>
#include <cstring>
#include <tuple>
#include <utility>
#include <list>
#include <cmath>
#include <unordered_map>

using namespace std;

typedef long long LL;
typedef vector<int> Array;
typedef pair<int, int> P;

const int INF = 1 << 29;
const LL MOD = 100000;
#define rep(i,n) for(int i=0;i<(int)n;++i)
#define all(c) (c).begin(), (c).end()

struct edge{ int to, cost; edge(int t, int c) :to(t), cost(c){} };

int main()
{
	//while (cin >> n)
	stringstream ss;
	//ss << "result" << i + 1 << ".txt";
	//FILE* fp_out = freopen(ss.str().c_str(), "w", stdout);

	int n, m;
	while (cin >> n >> m && n)
	{
		vector<vector<int>> times(m, vector<int>(m, INF));
		vector<vector<int>> costs(m, vector<int>(m, INF));
		rep(i, n)
		{
			int a, b, c, t;
			cin >> a >> b >> c >> t;
			a--; b--;
			costs[a][b] = costs[b][a] = c;
			times[a][b] = times[b][a] = t;
		}

		rep(k, m) rep(i, m) rep(j, m)
		{
			costs[i][j] = min(costs[i][j], costs[i][k] + costs[k][j]);
		}

		int k; cin >> k;
		rep(i, k)
		{
			int p, q, r; cin >> p >> q >> r;
			p--; q--;
			cout << (r ? costs[p][q] : times[p][q]) << endl;
		}
	}

	return 0;
}