Go: // Warshall–Floyd Algorithm

package main

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

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
				} else {
					c_dist[i][j] = c_matrix[i][j]
				}
				if c_matrix[i][j] == 0{
					c_prev[i][j] = -1
				} else {
					c_prev[i][j] = i
				}
				if t_matrix[i][j] == 0{
					t_dist[i][j] = INF
				} else {
					t_dist[i][j] = t_matrix[i][j]
				}
				if t_matrix[i][j] == 0{
					t_prev[i][j] = -1
				} else {
					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]
					t_newlen := t_dist[i][k] + t_dist[k][j]
					if c_newlen < c_dist[i][j] {
						c_dist[i][j] = c_newlen
						c_prev[i][j] = c_prev[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 <cstdio>
#include <cstring>
#include <cstdlib>
#include <cmath>
#include <complex>
#include <string>
#include <sstream>
#include <algorithm>
#include <vector>
#include <queue>
#include <stack>
#include <functional>
#include <iostream>
#include <map>
#include <set>
using namespace std;
typedef pair<int,int> P;
#define pu push
#define pb push_back
#define mp make_pair
#define eps 1e-7
#define INF 200000000
#define EQ(a,b) (abs((a)-(b))<EPS)
int n,m;
int mintime[100][100],mincost[100][100];
void warshall_floyd()
{
	for(int k=0;k<m;k++)
	{
		for(int i=0;i<m;i++)
		{
			for(int j=0;j<m;j++)
			{
				mincost[i][j]=min(mincost[i][j],mincost[i][k]+mincost[k][j]);
				mintime[i][j]=min(mintime[i][j],mintime[i][k]+mintime[k][j]);
			}
		}
	}
	return;
}
int main()
{
	while(1)
	{
		cin >> n >> m;
		if(n==0&&m==0)break;
		for(int i=0;i<m;i++)
		{
			for(int j=0;j<m;j++)
			{
				if(i==j)
				{
					mintime[i][j]=0;
					mincost[i][j]=0;
				}
				else
				{
					mintime[i][j]=INF;
					mincost[i][j]=INF;
				}
			}
		}
		for(int i=0;i<n;i++)
		{
			int a,b,cost,time;
			cin >> a >> b >> cost >> time;
			mincost[a-1][b-1]=cost;
			mincost[b-1][a-1]=cost;
			mintime[a-1][b-1]=time;
			mintime[b-1][a-1]=time;
		}
		warshall_floyd();
		/*
		for(int i=0;i<m;i++)
		{
			for(int j=0;j<m;j++)
			{
				cout << mincost[i][j] << ' ';
			}
			cout << endl;
		}
		for(int i=0;i<m;i++)
		{
			for(int j=0;j<m;j++)
			{
				cout << mintime[i][j] << ' ';
			}
			cout << endl;
		}
		*/
		int k1;
		cin >> k1;
		for(int i=0;i<k1;i++)
		{
			int p,q,r;
			cin >> p >> q >> r;
			if(r==0)
			{
				cout << mincost[p-1][q-1] << endl;
			}
			else
			{
				cout << mintime[p-1][q-1] << endl;
			}
		}
	}
	return 0;
}

C++: #include <iostream>
#include <vector>
using namespace std;
#define REP(i,n) for (int i=0; i<(n); ++i)

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

int main() {
    int n, m;
    while (cin >> n >> m, n || m) {
        vector<edge> edges;
        int a, b, v, u;
        REP(i,n) {
            cin >> a >> b >> v >> u;
            edges.push_back((edge){ a, b, v, u });
        }
        int d[2][101][101];
        REP(i,2) REP(j,101) REP(k,101) {
            d[i][j][k] = (j == k ? 0 : 1e8);
        }
        REP(i,101) REP(j,101) for (auto &e : edges) {
            d[0][j][e.to] = min(d[0][j][e.to], d[0][j][e.from] + e.cost);
            d[0][j][e.from] = min(d[0][j][e.from], d[0][j][e.to] + e.cost);
            d[1][j][e.to] = min(d[1][j][e.to], d[1][j][e.from] + e.time);
            d[1][j][e.from] = min(d[1][j][e.from], d[1][j][e.to] + e.time);
        }
        int k, p, q, r;
        cin >> k;
        REP(i,k) {
            cin >> p >> q >> r;
            cout << d[r][p][q] << endl;
        }
    }
    return 0;
}

C++: #include<iostream>
#include<cstdio>
#include<algorithm>
#include<functional>
#include<queue>

using namespace std;

#define max_n 3000
#define INF (max_n+100)*(1000+1000)

struct edge{
	int to,cost[2]; ///cost[0] 最少金額 cost[1] 最短距離
};

typedef pair<int,int> P;

int main(void){
	int n,m,k;
	int p,q,r;
	int a,b,c,t;
	vector<edge> N[max_n];
	edge e;
	int d[max_n];
	priority_queue<P,vector<P>,greater<P> > que;
	int v;
	P pi;

	while(1){

		cin>>n>>m;
		if(n==0&&m==0) break;

		for(int i=0;i<n;i++){
			cin>>a>>b>>c>>t;
			e.to=b,e.cost[0]=c,e.cost[1]=t;
			N[a].push_back(e);
			e.to=a;
			N[b].push_back(e);
		}
	
		cin>>k;

		for(int i=0;i<k;i++){

			cin>>p>>q>>r;

			fill(d,d+n,INF);
			d[p]=0;
			que.push(P(0,p));
			while(!que.empty()){
				pi=que.top();
				que.pop();
				v=pi.second;
				if(d[v]<pi.first) continue;
				for(int j=0;j<N[v].size();j++){
					e=N[v][j];
					if(d[e.to]>d[v]+e.cost[r]){
						d[e.to]=d[v]+e.cost[r];
						que.push(P(d[e.to],e.to));
					}
				}
			}

			cout<<d[q]<<endl;;

		}

	}

	return 0;
}