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 <functional>
#include <algorithm>
#include <iostream>
#include <numeric>
#include <iomanip>
#include <utility>
#include <cstdlib>
#include <sstream>
#include <bitset>
#include <vector>
#include <cstdio>
#include <ctime>
#include <queue>
#include <deque>
#include <cmath>
#include <stack>
#include <list>
#include <map>
#include <set>

using namespace std;

typedef vector<int> vi;
typedef pair<int,int> pii;
typedef long long ll;

#define dump(x)  cerr << #x << " = " << (x) << endl
#define rep(i,n) for(int i=0;i<(n);i++)
#define all(a)  (a).begin(),(a).end()
#define pb push_back
#define sz size()

const double EPS = 1e-10;
const int INF = 100000000;

int c[200][200];
int t[200][200];
int n,m;


void wf(){
    rep(k,m){
        rep(i,m){
            rep(j,m){
                c[i][j]=min(c[i][j],c[i][k]+c[k][j]);
                t[i][j]=min(t[i][j],t[i][k]+t[k][j]);

            }
        }
    }
}


int main(){
    while(cin>>n>>m){
        rep(i,200){
            rep(j,200){
                if(i==j){
                    c[i][j]=0;
                    t[i][j]=0;
                }
                else{
                    c[i][j]=INF;
                    t[i][j]=INF;
                }
            }
        }
        
        if(n==0 && m==0)break;
        
        rep(i,n){
            int a,b,z,d;
            cin>>a>>b>>z>>d;
            a--;b--;
            c[a][b]=z;
            c[b][a]=z;
            t[a][b]=d;
            t[b][a]=d;
        }
        wf();
        int k;
        cin>>k;
        rep(i,k){
            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<iostream>
#include<algorithm>
using namespace std;
int main(){
  const int MAX = 1e5;
  for(int n,m;cin>>n>>m,n;){
    int cost[m][m];
    int time[m][m];
    for(int i=0;i<m;i++){
      for(int j=0;j<m;j++){
	cost[i][j] = MAX;
	time[i][j] = MAX;
      }
    }
    int a,b,c,t;
    for(int i=0;i<n;i++){
      cin>>a>>b>>c>>t;
      cost[max(a-1,b-1)][min(a-1,b-1)] = c;
      time[max(a-1,b-1)][min(a-1,b-1)] = t;
    }
    for(int k=0;k<m;k++){
      for(int i=0;i<m;i++){
	for(int j=0;j<=i;j++){
	  if(cost[i][j]>cost[max(i,k)][min(i,k)]+cost[max(k,j)][min(j,k)])
	    cost[i][j] = cost[max(i,k)][min(i,k)]+cost[max(k,j)][min(j,k)];
	  if(time[i][j]>time[max(i,k)][min(i,k)]+time[max(k,j)][min(j,k)])
	    time[i][j] = time[max(i,k)][min(i,k)]+time[max(k,j)][min(j,k)];
	}
      }
    }
    int l,r;
    cin>>l;
    for(int i=0;i<l;i++){
      cin>>a>>b>>r;
      if(r)
	cout<<time[max(a-1,b-1)][min(a-1,b-1)]<<endl;
      else
	cout<<cost[max(a-1,b-1)][min(a-1,b-1)]<<endl;      
    }
  }
  return 0;
}

C++: #include <iostream>

const int INF = 1 << 29;

using namespace std;

int main(void){
	int n,m;
	
	while(cin >> n >> m){
		if((n|m) == 0) break;
		int dist[m][m];
		int time[m][m];
		
		for(int i=0;i<m;i++){
			for(int j=0;j<m;j++){
				if(i == j){
					dist[i][j] = 0;
					time[i][j] = 0;
				}else{
					dist[i][j] = INF;
					time[i][j] = INF;
				}
			}
		}
		
		int s, e, cd, ct;
		for(int i=0;i<n;i++){
			cin >> s >> e >> cd >> ct;
			dist[s-1][e-1] = cd;
			dist[e-1][s-1] = cd;
			time[s-1][e-1] = ct;
			time[e-1][s-1] = ct;
		}
		
		//WF
		for(int k=0;k<m;k++){
			for(int i=0;i<m;i++){
				for(int j=0;j<m;j++){
					dist[i][j] = min(dist[i][j], dist[i][k] + dist[k][j]);
					time[i][j] = min(time[i][j], time[i][k] + time[k][j]);
				}
			}
		}
		
		int cases,type;
		cin >> cases;
		for(int i=0;i<cases;i++){
			cin >> s >> e >> type;
			if(type == 0){
				cout << dist[s-1][e-1] << endl;
			}else{
				cout << time[s-1][e-1] << endl;
			}
		}
	}
}

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

using namespace std;

struct RequestObj {
	int begin, end, type;
};

int n, m;//???,???????????°
int k;//????????¨????????°
int time_table[100][100];
int cheap_table[100][100];
RequestObj request[200];


const int INF = 10000000;

int main() {
	while (cin >> n >> m, n * m) {

		for (int i = 0; i < m; i++)for (int j = 0; j < m; j++)time_table[i][j] = INF, cheap_table[i][j] = INF;
		
		for (int i = 0; i < n; i++) {
			int a, b;
			cin >> a >> b;
			cin >> cheap_table[a - 1][b - 1] >> time_table[a - 1][b - 1];
			cheap_table[b - 1][a - 1] = cheap_table[a - 1][b - 1];
			time_table[b - 1][a - 1] = time_table[a - 1][b - 1];
		}
		cin >> k;
		for (int i = 0; i < k; i++) {
			cin >> request[i].begin >> request[i].end >> request[i].type;
		}
		for (int i = 0; i < m; i++) {
			for (int j = 0; j < m; j++) {
				for (int k = 0; k < m; k++) {
					if (cheap_table[j][i] + cheap_table[i][k] < cheap_table[j][k]) {
						cheap_table[j][k] = cheap_table[j][i] + cheap_table[i][k];
					}
				}
			}
		}

		for (int i = 0; i < m; i++) {
			for (int j = 0; j < m; j++) {
				for (int k = 0; k < m; k++) {
					if (time_table[j][i] + time_table[i][k] < time_table[j][k]) {
						time_table[j][k] = time_table[j][i] + time_table[i][k];
					}
				}
			}
		}
		for (int i = 0; i < k; i++) {
			if (request[i].type == 0) {
				cout << cheap_table[request[i].begin - 1][request[i].end - 1] << endl;
			}
			else {
				cout << time_table[request[i].begin - 1][request[i].end - 1] << endl;
			}
		}

		for (int i = 0; i < m; i++)for (int j = 0; j < m; j++)time_table[i][j] = INF, cheap_table[i][j] = INF;

	}
	return 0;
}