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 <iostream>
#include <vector>
#include <algorithm>
#include <cstdio>
#define _m_ 1
const int INF = 1e9;

int cost[101][101];
int tim[101][101];
int d[101];
bool used[101];
int V;

void dijkstra(int s, int o){
	std::fill(d, d + V, INF);
	std::fill(used, used + V, false);
	d[s] = 0;
	while(_m_){
		int v = -1;
		for(int u = 0; u < V; ++u){
			if(!used[u] && (v == -1 || d[u] < d[v])) v = u;
		}
		if(v == -1)break;
		used[v] = true;
		if(o == 0){
			for(int u = 0; u < V; ++u){
				d[u] = std::min(d[u], d[v] + cost[v][u]);
			}
		}else {
			for(int u = 0; u < V; ++u){
				d[u] = std::min(d[u], d[v] + tim[v][u]);
			}
		}
	}
}

int main(){
	int n, m;
	while(scanf("%d %d",&n,&m), n+m){
		for(int i=0;i<n;++i){
			for(int j=0;j<n;++j){
				cost[i][j]=INF;
				tim[i][j]=INF;
			}
		}
		for(int i = 0; i < n; ++i){
			int a, b, co, ti;
			scanf("%d %d %d %d",&a, &b, &co, &ti);
			a--,b--;
			cost[a][b] = co, cost[b][a] = co;
			tim[a][b] = ti, tim[b][a] = ti;
		}
		V = m;
		int k;
		scanf("%d", &k);
		for(int i = 0; i < k; ++i){
			int p, q, r;
			scanf("%d %d %d", &p, &q, &r);
			p--, q--;
			dijkstra(p, r);
			printf("%d\n", d[q]);
		}
	}
}

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

#define V_MAX 100
using namespace std;

struct edge { 
    int to, cost; 
    edge(int to, int cost) : to(to), cost(cost){} 
};

vector<edge> money_g[V_MAX];
vector<edge> time_g[V_MAX];

int money_d[V_MAX], time_d[V_MAX];

#define INF 1000000

typedef pair<int, int> P; // cost, to
int min_money_cost(int from, int to) {
    priority_queue<P, vector<P>, greater<P> > q;
    fill(money_d, money_d+V_MAX, INF);
    money_d[from] = 0;
    q.push(P(0, from));

    while (!q.empty()) {
        P p = q.top(); q.pop();
        int v = p.second;
        if (money_d[v] < p.first) continue;
        for (int i = 0; i < money_g[v].size(); i++) {
            edge e = money_g[v][i];
            if (money_d[e.to] > money_d[v] + e.cost) {
                money_d[e.to] = money_d[v] + e.cost;
                q.push(P(money_d[e.to], e.to));
            }
        }
    }

    return money_d[to];
}

int min_time_cost(int from, int to) {
    priority_queue<P, vector<P>, greater<P> > q;
    fill(time_d, time_d+V_MAX, INF);
    time_d[from] = 0;
    q.push(P(0, from));

    while (!q.empty()) {
        P p = q.top(); q.pop();
        int v = p.second;
        if (time_d[v] < p.first) continue;
        for (int i = 0; i < time_g[v].size(); i++) {
            edge e = time_g[v][i];
            if (time_d[e.to] > time_d[v] + e.cost) {
                time_d[e.to] = time_d[v] + e.cost;
                q.push(P(time_d[e.to], e.to));
            }
        }
    }

    return time_d[to];
}

void init() {
    for (int i = 0; i < V_MAX; i++) {
        time_g[i].clear();
        money_g[i].clear();
    }
}

int main() {
    int n, m;
    while (cin >> n >> m, (n || m)) {
        init();
        for (int i = 0; i < n; i++) {
            int a, b, money, time;
            cin >> a >> b >> money >> time;
            money_g[a].push_back(edge(b, money));
            money_g[b].push_back(edge(a, money));
            time_g[a].push_back(edge(b, time));
            time_g[b].push_back(edge(a, time));
        }
        int k; cin >> k;
        for (int i = 0; i < k; i++) {
            int from, to, query_t;
            cin >> from >> to >> query_t;
            int res;
            if (query_t == 0) res = min_money_cost(from, to);
            else res = min_time_cost(from, to);
            cout << res << endl;
        }
    }
    return 0;
}

C++: #include <iostream>
#include <vector>
#include <algorithm>
using namespace std;
#define INF 1010001000
#define loop(i, n) for (int i = 1; i < n; i++)

int main()
{
int n, m; cin >> n >> m; m++;
vector<vector<int> > time(m,vector<int>(m,INF)), cost(m,vector<int>(m,INF));
loop(i, n+1){
int a,b,c,t; cin>>a>>b>>c>>t;
time[a][b]=t;time[b][a]=t;
cost[a][b]=c;cost[b][a]=c;
}
loop(k, m){loop(i, m){loop(i, m){
time[i][j]=min(time[i][j],time[i][k]+time[k][j]);
cost[i][j]=min(cost[i][j],cost[i][k]+cost[k][j]);
}}}
int k; cin>>k;
loop(i, k+1){
int p,q,r; cin>>p>>q>>r;
if(r) cout<<time[p][q]<<endl;
else cout<<cost[p][q]<<endl;
}
return 0;

}