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
			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
					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 <algorithm>
#include <map>
#include <vector>
#include <iostream>
#include <sstream>
#include <cstdio>
#include <cstring>
#include <cctype>
#include <cstdlib>
#include <cmath>
#include <string>
#include <queue>
#include <stack>
#include <set>
using namespace std;

#define REP(i,n) for(int i=0; i<n; ++i)
#define IREP(it,array) for(vector<int>::iterator it=array.begin(); it!=array.end(); ++it)
#define SREP(it,array) for(vector<string>::iterator it=array.begin(); it!=array.end(); ++it)

#define MP       make_pair
#define PB       push_back
#define ALL(x)   (x).begin(),(x).end()

const int INF = 1<<29;
const double EPS = 1e-9;
double zero(double d){
  return d < EPS ? 0.0 : d;
}

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


int main()
{
  cout.setf(ios::fixed, ios::floatfield);
  cout.precision(7);

  int n,m;
  cin >> n >> m;

  vector< vector<int> > cost(m+1, vector<int>(m+1,INF)),
    time(m+1, vector<int>(m+1,INF));

  REP(i,cost.size()){
    cost[i][i] = 0;
    time[i][i] = 0;
  }

  REP(i,n){
    int a,b,c,t;
    cin >> a >> b >> c >> t;
    cost[a][b] = c;
    cost[b][a] = c;
    time[a][b] = t;
    time[b][a] = t;
  }

  int k;
  cin >> k;
  REP(_tmp,k){
    int p,q,r;
    cin >> p >> q;
    if(p==0&&q==0)
      return 0;
    cin >> r;

    vector< vector<int> > data(m+1, vector<int>(m+1,0));
    data = r ? time : cost;

    deque<bool> reached(m+1,0);
    vector<int> dis(m+1,INF);
    dis[p] = 0;

    while(true){
      int minn = -1;
      REP(i,reached.size()){
	if( ! reached[i] ){
	  if( minn==-1 || dis[minn] > dis[i] ){
	    minn = i;
	  }
	}
      }
      if( minn == q )
	break;

      reached[minn] = true;
      REP(i,data[minn].size()){
	dis[i] = min( dis[minn] + data[minn][i], dis[i] );
      }
    }

    cout << dis[q] << endl;
  }

  return 0;
}

C++: #include<iostream>
#include<vector>
using namespace std;
class NextNodesData
{
public:	
	int nextNodesName;
	int nextNodesMany;
	int nextNodesTime;
};
class Nodes
{
public:
	vector<NextNodesData> nextNodes;
	int name;
	int minValue;
	bool fixed;
};

int main()
{
	int N, M;
	cin >> N >> M;
	vector<Nodes> nodesList;
	for(int i = 0; i < M; i++)
	{
		Nodes nodes;
		nodes.name = i+1;
		nodesList.push_back(nodes);
	}
	for(int i = 0; i < N; i++)
	{
		int Start;
		int End;
		int Many;
		int Time;
		cin >> Start >> End >> Many >> Time;

		NextNodesData nodes;
		nodes.nextNodesName = End;
		nodes.nextNodesMany = Many;
		nodes.nextNodesTime = Time;
		nodesList[Start - 1].nextNodes.push_back(nodes);
	}

	int Query;
	cin >> Query;

	for(int i = 0; i < Query; i++) 
	{
		
		 //???????????????
		for(int j = 0; j < nodesList.size(); j++)
		{
			nodesList[j].fixed = false;
		}
		int Start;
		int End;
		int mode;
		
		cin >> Start >> End;
		cin >> mode;

		if(Start == End)
		{
			cout << 0 << endl;
			continue;
		}

		nodesList[Start - 1].fixed = true;
		nodesList[Start - 1].minValue = 0;
		int nextFixedNodesName = Start;

		

		vector<Nodes> candidate;
		while(1)
		{
			//??????????¢????????????°??????????´????????????????????????¨???????????????????????????
			for(int j = 0; j < nodesList[nextFixedNodesName - 1].nextNodes.size(); j++)
			{
				
				Nodes obj;
				obj.name = nodesList[nextFixedNodesName - 1].nextNodes[j].nextNodesName;
				//??¢??????????????????????????????????????????????????????
				if(nodesList[obj.name - 1].fixed == true)
				{
					continue;
				}
				if(mode == 0)
				{
					obj.minValue = nodesList[nextFixedNodesName - 1].minValue + nodesList[nextFixedNodesName - 1].nextNodes[j].nextNodesMany;
				}
				else
				{
					obj.minValue = nodesList[nextFixedNodesName - 1].minValue + nodesList[nextFixedNodesName - 1].nextNodes[j].nextNodesTime;
				}
				//?¬???????????????????????????????????????????
				candidate.push_back(obj);				   
			}

			int minValue = 1001;
			int minName  = -1;
			//?¬????????????????????£???????????°???????????????¢???
			for(int j = 0; j < candidate.size(); j++)
			{
				if(candidate.size() == 0)
				{
					cout << 0 << endl;
				}
				if(candidate[j].minValue < minValue)
				{
					minValue = candidate[j].minValue;
					minName = candidate[j].name;
				}  
			}
			if(minName == -1)
			{
				cout << 0 << endl;
			}
			if(minName == End)
			{
				cout << minValue << endl;
				break;
			}
			nodesList[minName - 1].minValue = minValue;
			nodesList[minName - 1].fixed = true;
			nextFixedNodesName = minName;

			
			for(auto itr = candidate.begin(); itr != candidate.end();)
			{
				if(nodesList[itr->name - 1].fixed == true)
				{
					itr = candidate.erase(itr);
				}
				else
				{
					itr++;
				}
			}
		}	
		

	} 

	return 0;

}