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>

int adjacive[100][100][2];
const int INF=1000000000;

int dijkstra(int start,int goal,int type,int num);

int main()
{
	while(1)
	{
		int n,m,k;
		
		std::cin>>n>>m;
		
		if(n==0&&m==0)break;
		
		for(int i=0;i<m;i++)
		{
			for(int j=0;j<m;j++)
			{
				for(int k=0;k<2;k++)
				{
					adjacive[i][j][k]=INF;
				}
			}
		}
		
		for(int i=0;i<n;i++)
		{
			int a,b,c,t;
			std::cin>>a>>b>>c>>t;
			adjacive[a-1][b-1][0]=c;
			adjacive[b-1][a-1][0]=c;
			adjacive[a-1][b-1][1]=t;
			adjacive[b-1][a-1][1]=t;
		}
		
		std::cin>>k;
		
		for(int i=0;i<k;i++)
		{
			int result,p,q,r;
			std::cin>>p>>q>>r;
			result=dijkstra(p,q,r,m);
			std::cout<<result<<std::endl;
		}
	}
	return 0;
}

int dijkstra(int start,int goal,int type,int num)
{
	bool visited[100];
	int cost[100];
	for(int i=0;i<num;i++)
	{
		visited[i]=false;;
		cost[i]=INF;
	}
	
	cost[start-1]=0;
	
	while(1)
	{
		int u=-1;
		for(int i=0;i<num;i++)
		{
			if(!visited[i]&&(u==-1||cost[i]<cost[u]))
			{
				u=i;
			}
		}
		if(u==-1)break;
		
		visited[u]=true;
		for(int i=0;i<num;i++)
		{
			if(!visited[i])
			{
				cost[i] = cost[i] > cost[u] + adjacive[u][i][type] ? cost[u] + adjacive[u][i][type] : cost[i];
			}
		}
	}
	return cost[goal-1];
}

C++: #include <iostream>
#include <algorithm>
#define MAX_M 100
#define INF 1e9
using namespace std;

int dp_cost[MAX_M][MAX_M];
int dp_time[MAX_M][MAX_M];
int m;

void warshall_froyd(){
  for(int k=0;k<m;k++){
    for(int i=0;i<m;i++){
      for(int j=0;j<m;j++){
        dp_cost[i][j] = min(dp_cost[i][j], dp_cost[i][k] + dp_cost[k][j]);
        dp_time[i][j] = min(dp_time[i][j], dp_time[i][k] + dp_time[k][j]);
      }
    }
  }
}

int main(){
  int n;
  
  while(cin >> n >> m){
    if(n == 0 && m == 0) break;
    for(int i=0;i<m;i++){
      for(int j=0;j<m;j++){
        dp_time[i][j] = (i==j ? 0 : INF);
        dp_cost[i][j] = (i==j ? 0 : INF);
      }
    }
    
    for(int i=0;i<n;i++){
      int a,b,cost,time;
      cin >> a >> b >> cost >> time;
      a--;
      b--;
      dp_cost[a][b] = cost; dp_cost[b][a] = cost;
      dp_time[a][b] = time; dp_time[b][a] = time;
    }
    
    warshall_froyd();
    
    int k,p,q,r;
    cin >> k;
    for(int i=0;i<k;i++){
      cin >> p >> q >> r;
      p--; q--;
      cout << (r == 0 ? dp_cost[p][q] : dp_time[p][q]) << endl;
    }
  }
  return 0;
}

C++: #include<iostream>
#include<algorithm>
#include<vector>
#include<queue>

using namespace std;

const int INF=1e9;

//struct edge{int to,cost,time;};
struct edge{int cost,time;};

int main(){
	int n,m;
	cin >> n >> m;

	//vector<edge> es[n];
	edge es[m][m];
	for(int i=0;i<m;i++)for(int j=0;j<m;j++) es[i][j] = (edge){INF,INF};

	int a,b,cost,time;
	for(int i=0;i<n;i++){
		cin >> a >> b >> cost >> time;
	//	es[a].emplace_back((edge){b,cost,time});
		es[a-1][b-1] = (edge){cost,time};
		es[b-1][a-1] = es[a-1][b-1];
	}

	int d_cost[m][m];
	int d_time[m][m];
	for(int i=0;i<m;i++){
		for(int j=0;j<m;j++){
			d_cost[i][j] = es[i][j].cost;
			d_time[i][j] = es[i][j].time;
		}
	}

	for(int k=0;k<m;k++){
		for(int i=0;i<m;i++){
			for(int j=0;j<m;j++){
				d_cost[i][j] = min(d_cost[i][j],d_cost[i][k] + d_cost[k][j]);
				d_time[i][j] = min(d_time[i][j],d_time[i][k] + d_time[k][j]);
			}
		}
	}

	int k;
	cin >> k;
	for(int n=0;n<k;n++){
		int p,q,r;
		cin >> p >> q >> r;

		if(r==0) cout << d_cost[p-1][q-1] << "\n";
		else	cout << d_time[p-1][q-1] << "\n";
	}
	cin >> k >> k;

	return 0;
}

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

const int inf = 1e8;
int m,n;
//n経路の数（枝）　m駅の数（葉）
struct edge{
  int from,to,cost,time;
  edge(int from,int to,int cost,int time): from(from), to(to), cost(cost), time(time){}
};

vector<edge> es;
int shortest_path(int s,int e,int v){
  int d[m];
  for(int i = 0 ; i < n ; i ++)d[i] = inf;
  d[s] = 0 ;
  while(true){
    bool updata = false;
    for(int i = 0 ; i < n ; i ++){
      edge e = es[i];
      if(d[e.from] != inf && d[e.to]> d[e.from] + e.cost && v == 0){
	d[e.to] = d[e.from] + e.cost;
	updata = true;
      }

      if(d[e.from] != inf && d[e.to]> d[e.from] + e.time && v == 1){
	d[e.to] = d[e.from] + e.time;
	updata = true;
      }
    } 
    if(!updata) break;
  }
  return d[e];
}

int main(void){
  while(cin>>n>>m,m+n){
    es.clear();
    for(int i = 0 ; i < n ; i ++){
      int s,t,c,ti;
      cin>>s>>t>>c>>ti;
      s--; t--;
      es.push_back(edge(s,t,c,ti));
    }
    int num;
    cin>>num;
    for(int i = 0 ; i < num ;  i++){
      int s,t,v;
      cin>>s>>t>>v;
      s--; t--;
      //cout<<s <<" " << t << " " << v<<" ";
      continue;
      cout<<shortest_path(s,t,v)<<endl;
    }
  }
  
    
}