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<string>
#include<algorithm>
#include<list>
#include<set>
#include<map>
#include<queue>
#include<stack>
#include<numeric>
#include<vector>
#include<cstdio>
#include<climits>
#include<cfloat>
#include<cstring>
#define foreach(t,p,tit) for(t::iterator tit=p.begin();tit!=p.end();++tit)
#define rforeach(t,p) for(t::reverse_iterator it=p.rbegin();it!=p.rend();++it)
#define all(p) p.begin(),p.end()
#define rep(i,n) for(int i=0;i<n;i++)
using namespace std;
int costs[1010][1010];
int times[1010][1010];
int d[1010];
#define INF 10000
struct E
{
    int a,b,c;
    E(){};
    E(int a,int b,int c):a(a),b(b),c(c){};
};
#define MONEY 0
#define EKI 1

int main()
{
    int n,m;
    while(cin>>n>>m)
    {
        if(n==0&&m==0)break;
        memset(costs,INF,sizeof(costs));
        memset(times,INF,sizeof(times));
        vector<E> cs;
        vector<E> ts;
        int a,b,c,t;
        rep(i,n)
        {
            cin>>a>>b>>c>>t;
            costs[a][b] = c; costs[b][a] = c;
            times[a][b] = t; times[b][a] = t;
            cs.push_back(E(a,b,c));
            cs.push_back(E(b,a,c));
            ts.push_back(E(a,b,t));
            ts.push_back(E(b,a,t));
        }
        rep(i,m)
        {
            costs[i][i] = 0;
            times[i][i] = 0;
        }
        int k,p,q,r;
        cin>>k;
        rep(i,k)
        {
            memset(d,INF,sizeof(d));
            cin >> p >> q >> r;
            d[p] = 0;
            if(r==MONEY)
            {
                //rep(j,n*2){if(cs[j].a == p) d[cs[j].b] = cs[j].c;}
                while(true)
                {
                    bool update = false;
                    rep(j,n*2)
                    {
                        //cout <<"edge"<< j<<cs[j].a<<"to"<<cs[j].b << endl;

                        if( (d[ cs[j].a] != INF) && d[cs[j].b] > d[cs[j].a] + cs[j].c)
                        {
                            d[cs[j].b] = d[ cs[j].a] + cs[j].c;
                            update = true;
                            //cout << "updated" <<d[cs[j].b] <<endl;
                        }
                    }
                    if(!update)break;
                }
                cout << d[q]<<endl;
            }
            else
            {
                //rep(j,n*2){if(ts[j].a == p) d[ts[j].b] = ts[j].c;}
                while(true)
                {
                    bool update = false;
                    rep(j,n*2)
                    {
                        if(d[ ts[j].a] != INF && d[ts[j].b] > d[ts[j].a] + ts[j].c)
                        {
                            d[ts[j].b] = d[ ts[j].a] + ts[j].c;
                            update = true;
                        }
                    }
                    if(!update)break;
                }
                cout << d[q]<<endl;
            }
        }
    }

    return 0;
}

C++: #include<iostream>
#include<set>
#define loop(i,a,b) for(int i=a;i<b;i++)
#define rep(i,a) loop(i,0,a)
#define INF 1e6
using namespace std;
int n,m,k,a,b,c,alt,p,q,r;
int cost[101][101],tm[101][101],d[101];
bool used[101];

void dfunc(int s,int r){
	d[s]=0;
	rep(i,101){
		used[i]=true;
		d[i]=INF;
	}
	while(1){
		int mem=INF,now=-1;
		rep(i,101){
			if(used[i] && mem>d[i]){
				now=i;
				mem=d[i];
			}
		}
		if(now==-1)break;
		used[now]=false;
		rep(i,101){
			if(r==0){
				if(cost[now][i]!=INF)d[i]=d[now]+cost[now][i];
			}else{
				if(tm[now][i]!=INF)d[i]=d[now]+tm[now][i];
			}
		}
	}
}

int main(){
	while(cin>>n>>m,n||m){
		rep(i,101)rep(j,101){
			cost[i][j]=INF;
			tm[i][j]=INF;
		}
		rep(i,n){
			cin>>a>>b>>c>>alt;
			a--;
			b--;
			cost[b][a]=cost[a][b]=c;
			tm[b][a]=tm[a][b]=alt;
		}
		cin>>k;
		rep(i,k){
			cin>>p>>q>>r;
			dfunc(p,r);
			cout<<d[q]<<endl;
		}
	}
	return 0;
}

C++: #include <iostream>
#include <cstdio>
#include <vector>
#include <utility>
#include <queue>
#include <functional>
#define N 101
#define INF 2000000000
using namespace std;

int dist[N];
typedef pair<int,int> pii;

std::vector<pii> e1[N];
std::vector<pii> e2[N];

int dijk1(int a,int b){
	dist[a]=0;
	std::priority_queue<pii> pq;
	for(int i=0;i<e2[a].size();i++){
		pq.push(e2[a][i]);
	}
	while(!pq.empty()){
		pii temp=pq.top();
		int now=temp.second;
		int c=temp.first;
		pq.pop();
		if(dist[now]!=INF)continue;
		dist[now]=c;
		if(now==b)break;
		for(int i=0;i<e2[now].size();i++){
				if(dist[e2[now][i].second]==INF) pq.push(make_pair(c+e2[now][i].first,e2[now][i].second));
		}
	}
	return -dist[b];
}

int dijk(int a,int b){
	dist[a]=0;
	std::priority_queue<pii> pq;
	for(int i=0;i<e1[a].size();i++){
		pq.push(e1[a][i]);
	}
	while(!pq.empty()){
		pii temp=pq.top();
		int now=temp.second;
		int c=temp.first;
		pq.pop();
		if(dist[now]!=INF)continue;
		dist[now]=c;
		if(now==b)break;
		for(int i=0;i<e1[now].size();i++){
			if(dist[e1[now][i].second]==INF) pq.push(make_pair(c+e1[now][i].first,e1[now][i].second));
		}
	}
	return -dist[b];
}

int main(void){
	int a,b,c,d;
	int n,m;
	while(cin>>n>>m,n||m){
		for(int i=0;i<n;i++){
			cin>>a>>b>>c>>d;
			e1[a].push_back(make_pair(-c,b));
			e2[a].push_back(make_pair(-d,b));
		}
		int k;
		cin>>k;
		while(k--){
			for(int i=1;i<=m;i++)dist[i]=INF;
			cin>>a>>b>>c;
			if(c) cout<<dijk1(a,b)<<endl;
			else cout<<dijk(a,b)<<endl;
			// for(int i=1;i<=m;i++)printf("dist[%d]:%d\n",i,dist[i]);
		}
	}
	return 0;
}