Go: // Warshall–Floyd Algorithm

package main

import (
	"bufio"
	"fmt"
	"os"
	"strconv"
	"strings"
)

var scanner = bufio.NewScanner(os.Stdin)

const INF = 0x7FFFFFFF

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;
  while(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] = time[i][i] = 0;
    }

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

    REP(i,cost.size()){
      REP(j,cost.size()){
	REP(k,cost.size()){
	  cost[j][k] = min( cost[j][k], cost[j][i] + cost[i][k] );
	  time[j][k] = min( time[j][k], time[j][i] + time[i][k] );
	}
      }
    }

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

      cin >> r;
      int res= r ? time[p][q] : cost[p][q];
      cout << res << endl;
    }
  }

  return 0;
}

C++: #include<iostream>
#include<string.h>
using namespace std;
#define WHITE 0
#define GLAY 1
#define BLACK 2
#define INF 9999
int kingaku(void);
int saitan(void);
int n,m,p,q;
int cost[101][101],timev[101][101];
int main()
{
	int a,b,c,t,k,r;
	while(1){
		memset(cost,INF,sizeof(cost));
		memset(timev,INF,sizeof(timev));
		cin >> n >> m;
		if(n==0 && m==0) break;
		for(int i=0;i<n;i++){
			cin >> a >> b >> c >> t;
			cost[a][b] = cost[b][a] = c;
			timev[a][b] = timev[b][a] = t;
		}
		cin >> k;
		for(int i=0;i<k;i++){
			cin >> p >> q >> r;
			if(r==0){
				cout << kingaku() << endl;
			}
			else if(r==1)
				cout << saitan() << endl;
		}
	}
	return 0;
}

int kingaku()
{
	int minv;
	int dd[101],color[101];

	for(int i=0;i<n;i++){
		dd[i] = INF;
		color[i] = WHITE;
	}
	dd[p] = 0;
	color[p] = GLAY;
	while(1){
		minv = INF;
		int u = -1;
		for(int i=1;i<=m;i++){
			if(minv > dd[i] && color[i] != BLACK ){
				u = i;
				minv = dd[i];
			}
		}
		if(u == -1) break;
		color[u] = BLACK;
		//cout << "C=" << u;
		for(int v=1;v<=m ;v++){
			if(color[v] != BLACK && cost[u][v] != INF){
				if(dd[v] > dd[u] + cost[u][v]){	
					dd[v] = dd[u] + cost[u][v];
				}
			}
		}
	}
	//for(int i=0;i<n;i++) cout << dd[i] << endl;
	return dd[q];
}

int saitan()
{
	int minv;
	int dd[101],color[101];

	for(int i=0;i<n;i++){
		dd[i] = INF;
		color[i] = WHITE;
	}
	dd[p] = 0;
	color[p] = GLAY;
	while(1){
		minv = INF;
		int u = -1;
		for(int i=0;i<n;i++){
			if(minv > dd[i] && color[i] != BLACK ){
				u = i;
				minv = dd[i];
			}
		}
		if(u == -1) break;
		color[u] = BLACK;
		for(int v=1;v<=m;v++){
			if(color[v] != BLACK && timev[u][v] != INF){
				if(dd[v] > dd[u] + timev[u][v]){	//d[v]:??????
					dd[v] = dd[u] + timev[u][v];
				}
			}
		}
	}
	//for(int i=0;i<n;i++) cout << dd[i] << endl;
	return dd[q];
}

C++: #include <iostream>
#include <vector>
#include <string.h>

using namespace std;

static const int TYPE_COST =0;
static const int TYPE_TIME =1;

class station{
public:
	int cost;
	bool visited;
	vector<int> edge_to;
	vector<int> edge_cost;
	vector<int> edge_time;
	
	 public:
		station() :  cost(-1), visited(false){}
		void add_to(int to, int cost, int time)
		{
			this->edge_to.push_back(to);
			this->edge_cost.push_back(cost);
			this->edge_time.push_back(time);
		}
};

int dijkstra(station* sta, int size, int from, int to, int type);
bool contain(vector<station> sta, station elem);
void reset(station* sta, int size);

int main(int argc, char** argv)
{
	while( 1 ){
		int n, m, from, to, cost, time, type;
		cin >> n;
		cin >> m;
		if(n==0 && m==0) break;
		
		station sta[m];
		for(int i=0; i<m; i++){
			sta[i] = station();
		}
		
		for(int i=0; i<n; i++){
			cin >> from;
			cin >> to;
			cin >> cost;
			cin >> time;
			sta[from-1].add_to(to-1, cost, time);
		}
		cin >> n;
		for(int i=0; i<n; i++){
			cin >> from;
			cin >> to;
			cin >> type;
			cout << dijkstra(sta, m, from-1, to-1, type) << endl;
			reset(sta, m);
		}
	}
	
	return 0;
}

int dijkstra(station* sta, int size, int start, int goal, int type)
{
	int to, cost;
	station done;
	vector<station> q;
	sta[start].cost = 0;
	q.push_back(sta[start]);
	
	while(!q.empty()){
		done = q[0];
		q.erase(q.begin());
		done.visited = true;
		
		for(int i=0; i<done.edge_to.size(); i++){
			to = done.edge_to[i];
			if(type==TYPE_COST) cost = done.cost + done.edge_cost[i];
			if(type==TYPE_TIME) cost = done.cost + done.edge_time[i];
			if(sta[to].cost < 0 || cost < sta[to].cost){
				sta[to].cost = cost;
				if(!contain(q, sta[to])){
					q.push_back(sta[to]);
				}
			}
		}	
	}
	
	return sta[goal].cost;
}

bool contain(vector<station> sta, station elem)
{
	int size = sta.size();
	bool is_match = false;
	for(int i=0; i<size; i++){
		if(memcmp(&sta[i], &elem, sizeof(station)) == 0){
			is_match = true;
			break;
		}
	}
	return is_match;
}

void reset(station* sta, int size)
{
	for(int i=0; i<size; i++){
		sta[i].visited = false;
		sta[i].cost = -1;
	}
}