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<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(nodesList[candidate[j].name - 1].fixed == true)
				{
					continue;
				}*/

				if(candidate[j].minValue < minValue)
				{
					minValue = candidate[j].minValue;
					minName = candidate[j].name;
				}
			}
			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;

}

C++: #include <iostream>
#include <vector>
#include <algorithm>
#include <sstream>
#include <string>
const int INF = 1<<28;
using namespace std;
string IntToString(int);
int StringToInt(string);
struct edje{
public:
  int from;
  int to;
  int cost;
  edje(int f,int t,int c){
    from = f;
    to = t;
    cost = c;
  }
};
void bellmanFord(vector<int> &map,vector<edje> &cost){
  for(int i = 0;i < map.size();i++){
    for(int j = 0;j < cost.size();j++){
      map[cost[j].to] = min(map[cost[j].to],map[cost[j].from] + cost[j].cost);
    }
  }
}
int main(){
  while(1){
    int n,m;
    cin >> n >> m;
    if(n == 0 && m == 0)break;
    vector<edje> cost;
    vector<edje> time;
    
    for(int i = 0;i < n;i++){
      int a,b,c,t;
      cin >> a >> b >> c >> t;
      edje cs(a-1,b-1,c);
      cost.push_back(cs);
      cs= edje(b-1,a-1,c);
      cost.push_back(cs);
      edje tm(a-1,b-1,t);
      time.push_back(tm);
      tm = edje(b-1,a-1,t);
      time.push_back(tm);
    }
    int k;
    cin >> k;
    for(int i = 0;i < k;i++){
      int s,g,q;
      cin >> s >> g >> q;
      vector<edje> tmp;
      if(q == 0) tmp = vector<edje>(cost);
      else if(q == 1) tmp = vector<edje>(time);
      vector<int> map(m,INF);
      //      cout << map[g-1] << endl;
      map[s-1] = 0;
      bellmanFord(map,tmp);
      cout << map[g-1] << endl;
      

    }
  }
  return 0;   
}
string IntToString(int number){
  stringstream ss;
  ss << number;
  return ss.str();
}
int StringToInt(string number){
  stringstream ss;
  ss << number;
  int numInt;
  ss >> numInt;
  return numInt;
  
}

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



int d[100];
bool used[100];

int n,m,k;
int INF=200000000;



int main(){

	int i,j;
	int a,b,c,e;

	int cost[100][100];
	int time[100][100];


	scanf("%d %d",&n,&m);

	fill((int*)cost,(int*)(cost+m),INF);
	fill((int*)time,(int*)(time+m),INF);

	/*
	fill(d,d+m,INF);
	memset(used,0,sizeof(used));
	*/

	for(i=0;i<n;i++){
		scanf("%d %d %d %d",&a,&b,&c,&e);
		a--;
		b--;
		cost[a][b]=cost[b][a]=c;
		time[a][b]=time[b][a]=e;
	}

	scanf("%d",&k);

	for(i=0;i<k;i++){
	//for(;;){
		scanf("%d %d %d",&a,&b,&c);
		a--;
		b--;
		
		fill(d,d+m,INF);
		fill(used,used+m,false);

		d[a]=0;
		
		
		while(true){
			int v=-1;
			
			//printf("-\n");

			for(j=0;j<m;j++){
				if(!used[j] && (v==-1 || d[j]<d[v])) v=j;
			}	
			
			if(v==-1)break;
			used[v]=true;

			if(c) for(j=0;j<m;j++) d[j]=min(d[j],d[v]+time[v][j]);
			else  for(j=0;j<m;j++) d[j]=min(d[j],d[v]+cost[v][j]);
		}
		printf("%d\n",d[b]);
		
		

	}
	scanf("%d %d",&a,&b);
	

	return 0;
}