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 <bits/stdc++.h>
using namespace std;
typedef pair<int,int > P;
const int INF = 1 << 30;
int Dijkstra(int s,int g,int r);

int m,n;

int min_cost[2][111];

typedef struct{
  vector<int>edge_to;
  vector<int>edge_cost[2];
}Node_data;

Node_data Graph[111];

priority_queue<P ,vector< P >, greater< P > >que;

int main(){
  int a,b,c,d,k;
  int s,g,r;
  while(1){
    cin >> m >> n;
    if(m == 0 && n == 0)break;
    for(int i = 0;i < m;i++){
      scanf("%d %d %d %d",&a,&b,&c,&d);
      Graph[a - 1].edge_to.push_back(b - 1);
      Graph[a - 1].edge_cost[0].push_back(c);
      Graph[a - 1].edge_cost[1].push_back(d);
      Graph[b - 1].edge_to.push_back(a - 1);
      Graph[b - 1].edge_cost[0].push_back(c);
      Graph[b - 1].edge_cost[1].push_back(d);
    }
    cin >> k;
    for(int i = 0;i < k;i++){

      cin >> s >> g >> r;

      for(int j = 0;j < 111;j++){
	min_cost[0][j] = INF;
	min_cost[1][j] = INF;
      }
      cout << Dijkstra(s - 1,g - 1,r) << endl;
    }
  }
  return(0);
}

int Dijkstra(int s,int g,int r){
  int node,cost;
  int newnode,newcost;
  min_cost[r][s] = 0;
  P a;
  a.first = 0;
  a.second = s;
  que.push(a);
  while(!que.empty()){
    node = que.top().second;
    cost = que.top().first;
    que.pop();
    if(node == g)return cost;
    if(cost > min_cost[r][node])continue;
    for(int i = 0;i < Graph[node].edge_to.size();i++){
      newnode = Graph[node].edge_to[i];
      newcost = cost + Graph[node].edge_cost[r][i];
      if(min_cost[r][newnode] > newcost){
	min_cost[r][newnode] = newcost;
	a.first = newcost;
	a.second = newnode;
	que.push(a);
      }
    }
  }
  return -1;
}

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

#define REP(i, n) for(int i = 1; i <= n; i ++)

using namespace std;

typedef pair<int, int> pii;
const int UNDEFINED = (int)1e6;
int n;

int dijkstra(int, int, vector<vector<int> >);

int main(void){
    for(int m; cin >> m >> n, n;){
        vector<vector<int> > costMap(n + 1);
        vector<vector<int> > timeMap(n + 1);

        REP(i, n){
            costMap[i].resize(n + 1);
            timeMap[i].resize(n + 1);
            REP(j, n){
                costMap[i][j] = timeMap[i][j] = UNDEFINED;
            }
        }

        while(m --){
            int a, b, cost, time;
            cin >> a >> b >> cost >> time;
            costMap[a][b] = cost;
            costMap[b][a] = cost;
            timeMap[a][b] = time;
            timeMap[b][a] = time;
        }

        int k; cin >> k;
        while(k --){
            int s, g, mode;
            cin >> s >> g >> mode;

            cout << dijkstra(s, g, ((!mode) ? costMap:timeMap)) << endl;
        }
    }

    return 0;
}

int dijkstra(int s, int g, vector<vector<int> > data){
    vector<bool> used(n + 1);
    REP(i, n) used[i] = false;

    vector<int> d(n + 1);
    REP(i, n) d[i] = (i != s) ? UNDEFINED:0;

    while(1){
        int v = UNDEFINED;
        REP(i, n) if(!used[i] && (v == UNDEFINED || d[i] < d[v])) v= i;
        if(v == UNDEFINED) break;
        used[v] = true;

        REP(i, n) d[i] = min(d[i], d[v] + data[v][i]);
    }

    return d[g];
}

C++: #include <iostream>
#include <algorithm>
#include <string>
#include <vector>

using namespace std;

#define FOR(i,a,b) for(int i=(a);i<(b);++i)
#define REP(i,n)  FOR(i,0,n)
#define INF 11451400



int main(){
	while(true){
		int lineL, statL;
		cin >> lineL >> statL;
		if(lineL==0&&statL==0){return 0;}

		long leastCosts[statL][statL];
		long leastTimes[statL][statL];
		FOR(aStat,0,statL){
			FOR(bStat,0,statL){
				if(aStat==bStat){
					leastCosts[aStat][bStat] = 0;
					leastTimes[aStat][bStat] = 0;
				}else{
					leastCosts[aStat][bStat] = INF;
					leastTimes[aStat][bStat] = INF;
				}
			}
		}

		REP(lineI,lineL){
			int naStat,nbStat,nCost,nTime;
			cin >> naStat >> nbStat >> nCost >> nTime;
			naStat -=1; nbStat -=1;
			FOR(aStat,0,statL){
				FOR(bStat,0,statL){
					leastCosts[aStat][bStat] = min(leastCosts[aStat][bStat] , leastCosts[aStat][naStat]+nCost+leastCosts[nbStat][bStat]);
					leastCosts[aStat][bStat] = min(leastCosts[aStat][bStat] , leastCosts[aStat][nbStat]+nCost+leastCosts[naStat][bStat]);
					leastTimes[aStat][bStat] = min(leastTimes[aStat][bStat] , leastTimes[aStat][naStat]+nTime+leastTimes[nbStat][bStat]);
					leastTimes[aStat][bStat] = min(leastTimes[aStat][bStat] , leastTimes[aStat][nbStat]+nTime+leastTimes[naStat][bStat]);
				}
			}
		}

		int reqL;
		cin >> reqL;
		REP(reqI,reqL){
			int aStat,bStat,costOrTime;
			cin >> aStat >> bStat >> costOrTime;
			aStat-=1;bStat-=1;
			if(costOrTime==0){cout<<leastCosts[aStat][bStat]<<endl;};
			if(costOrTime==1){cout<<leastTimes[aStat][bStat]<<endl;};
		}
	}
}