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 <algorithm>
#define INF (1<<21)
using namespace std;
int cost[101][101];
int t_cost[101][101];
int n,m;
void warshall_floyd(){
  for(int i = 0 ; i < m ; i++ ){
    for(int j = 0 ; j < m ; j++ ){
      for(int k = 0 ; k < m ; k++ ){
	cost[i][j] = min(cost[i][j],cost[i][k] + cost[k][j]);
	t_cost[i][j] = min(t_cost[i][j],t_cost[i][k] + t_cost[k][j]);
      }
    }
  }
}

void input(){
  for(int i = 0 ; i < n ; i++ ){
    int a,b,c,d;
    cin >> a >> b >> c >> d;
    cost[a][b] = cost[b][a] = c;
    t_cost[a][b] = t_cost[b][a] = d;  
  }
}

void init(){
  for(int i = 0  ; i < m ; i++ ){
    for(int j = 0  ; j < m ; j++ ){
      if(i == j){
	cost[i][j] = 0;
	t_cost[i][j] = 0;
      }else{
	cost[i][j] = INF; 
	t_cost[i][j] = INF; 
      }
    }
  }
}

int main(){

  while(cin >> n >> m , n+m ){
    m++;
    init();
    input();
    warshall_floyd();
    int k;
    cin >> k;
    for(int i = 0 ; i < k ; i++ ){
      int from,to,r;
      cin >> from >> to >> r; 
      if(r == 0){
	cout << cost[from][to] << endl;
      } else {
	cout << t_cost[from][to] << endl;
      }
    }
  }
  return 0;
}

C++: // 2011/08/02 Tazoe

#include <iostream>
using namespace std;

int main()
{
	while(true){
		int n, m;
		cin >> n >> m;
		if(n==0&&m==0)
			break;

		int C[100][100];
		int T[100][100];
		for(int i=0; i<m; i++)
			for(int j=0; j<m; j++)
				if(i==j)
					C[i][j] = T[i][j] = 0;
				else
					C[i][j] = T[i][j] = 100000;

		for(int i=0; i<n; i++){
			int a, b, c, t;
			cin >> a >> b >> c >> t;
			C[a-1][b-1] = C[b-1][a-1] = c;
			T[a-1][b-1] = T[b-1][a-1] = t;
		}

		// tChÌASY
		for(int h=0; h<m; h++){
			for(int i=0; i<m; i++){
				for(int j=0; j<m; j++){
					if(C[i][j]>C[i][h]+C[h][j])
						C[i][j] = C[i][h]+C[h][j];
					if(T[i][j]>T[i][h]+T[h][j])
						T[i][j] = T[i][h]+T[h][j];
				}
			}
		}

		int k;
		cin >> k;

		for(int i=0; i<k; i++){
			int p, q, r;
			cin >> p >> q >> r;
			if(r==0)
				cout << C[p-1][q-1] << endl;
			else
				cout << T[p-1][q-1] << endl;
		}
	}

	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++){
		if(i>0){printf("\n");}
		int p,q,r;
		scanf("%d %d",&p,&q);
		if(p==0 && q==0){
			return 0;
		}
		scanf("%d",&r);
		printf("%d",solve(p,q,r));
	}
	return 0;
}

int solve(const int p,const int q,const int r){
	const int INF = 2147483647;
	int *a = new int[m+1];
	for(int i=0;i<=m;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++: #include<iostream>

using namespace std;

int main(){
	int cost[101][101];
	int tims[101][101];
	
	while(1){
		int n,m;
		cin>>n>>m;
		if(n==0){
			break;
		}
		for(int i=0;i<101;i++){
			for(int j=0;j<101;j++){
				cost[i][j]=tims[i][j]=210000000;
			}
		}
		
		for(int i=0;i<n;i++){
			int a,b,c,d;
			cin>>a>>b>>c>>d;
			cost[a][b]=cost[b][a]=c;
			tims[a][b]=tims[b][a]=d;
		}
		
				for(int k=1;k<=m;k++){
		for(int i=1;i<=m;i++){
			for(int j=1;j<=m;j++){
					cost[i][j]=min(cost[i][j],cost[i][k]+cost[k][j]);
					tims[i][j]=min(tims[i][j],tims[i][k]+tims[k][j]);
				}
			}
		}
		
		int l;
		cin>>l;
		for(int i=0;i<l;i++){
			int a,b,c;
			cin>>a>>b>>c;
			if(c==0){
				printf("%d\n",cost[a][b]);
			}else{
				
				printf("%d\n",tims[a][b]);
			}
		}
	}
}

C++: #include<iostream>
using namespace std;
#include<algorithm>
#include<string>
#define REP(i,a) for(int  i=0;i<a;i++)
int A[101][101];
int B[101][101];
int main(){
	int a,b=0,c=0,d,n,m;	
	cin>>n>>m;
	while(n!=0||m!=0){
	REP(i,m){
		REP(j,m){
			A[i][j]=1001;
			B[i][j]=1001;
		}
		A[i][i]=0;
		B[i][i]=0;
	}
	REP(i,n){
	cin>>a>>b>>c>>d;
	A[a-1][b-1]=c;
	B[a-1][b-1]=d;	
	A[b-1][a-1]=c;
	B[b-1][a-1]=d;
	}
	REP(k,m){
		REP(i,m){
		if(i==k) continue;
	 		REP(j,m){
		if(i==j)continue;
		A[i][j]=min(A[i][j],A[i][k]+A[k][j]);
		B[i][j]=min(B[i][j],B[i][k]+B[k][j]);
		A[j][i]=A[i][j];
		B[j][i]=B[i][j];
			}
		}	
	}
	cin>>n;
	REP(i,n){
	cin>>a>>b>>c;
	if(c==0) cout<<A[a-1][b-1]<<endl;
	else cout<<B[a-1][b-1]<<endl;
	}
	cin>>n>>m;
	}
	return 0;
}