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 <algorithm>

#define INF 114514810
#define MAX 100

int n, m, k;
int ti[MAX][MAX], co[MAX][MAX];

int main(){
    while(scanf("%d %d", &n, &m) != EOF){
        if(n == 0 && m == 0) break;

        int a, b, c, t;
        for(int i = 0; i < m; i++){
            for(int j = 0; j < m; j++){
                ti[i][j] = INF;
                co[i][j] = INF;
            }
        }

        for(int i = 0; i < n; i++){
            scanf("%d %d %d %d", &a, & b, &c, &t);
            a--; b--;

            ti[a][b] = ti[b][a] = t;
            co[a][b] = co[b][a] = c;
        }

        for(int k = 0; k < m; k++){
            for(int i = 0; i < m; i++){
                for(int j = 0; j < m; j++){
                    co[i][j] = std::min(co[i][j], co[i][k] + co[k][j]);
                    ti[i][j] = std::min(ti[i][j], ti[i][k] + ti[k][j]);
                }
            }
        }

        scanf("%d", &k);
        int p, q, r;
        for(int i = 0; i < k; i++){
            scanf("%d %d %d", &p, &q, &r);
            p--; q--;

            if(r == 0) printf("%d\n", co[p][q]);
            else if(r == 1) printf("%d\n", ti[p][q]);
        }
    }
    return 0;
}

C++: #include <iostream>
#include <cctype>
#include <algorithm>
#include <vector>
#include <map>
#include <queue>
#include <set>
#include <stack>
#include <utility>
#include <string>
#include <functional>
#include <cctype>
#include <cstring>
#include <cstdio>
#include <cstdlib>
#include <cmath>
typedef long long ll;
const int INF = 100000000, mod = 1000000007;
const ll LLINF = 1LL << 50;
using namespace std;

struct edge { int to, cos, tim; };
typedef pair<int, int> P;
vector<edge> G[105];
int n, m, k, cost[105], time[105];

void dijkstra(int s) {
    priority_queue<P, vector<P>, greater<P>> costque, timeque;
    fill(cost, cost + m + 1, INF);
    fill(time, time + m + 1, INF);
    cost[s] = 0;
    time[s] = 0;
    costque.push(P(s, 0));
    timeque.push(P(s, 0));

    while (!costque.empty()) {
        P p = costque.top();
        costque.pop();
        int v = p.first;
        if (cost[v] < p.second) continue;
        for (int i = 0; i < G[v].size(); i++) {
            edge e = G[v][i];
            if (cost[e.to] > cost[v] + e.cos) {
                cost[e.to] = cost[v] + e.cos;
                costque.push(P(e.to, cost[e.to]));
            }
        }
    }
    while (!timeque.empty()) {
        P p = timeque.top();
        timeque.pop();
        int v = p.first;
        if (time[v] < p.second) continue;
        for (int i = 0; i < G[v].size(); i++) {
            edge e = G[v][i];
            if (time[e.to] > time[v] + e.tim) {
                time[e.to] = time[v] + e.tim;
                timeque.push(P(e.to, time[e.to]));
            }
        }
    }
}

int main() {
    while (1) {
        cin >> n >> m;
        if (n == 0&&m == 0) break;
        for (int i = 0; i < n; i++) {
            int a, b, c, t;
            cin >> a >> b >> c >> t;
            edge tmp = { b,c,t };
            G[a].push_back(tmp);
        }
        cin >> k;
        for (int i = 0; i < k; i++) {
            int p, q, r;
            cin >> p >> q >> r;
            dijkstra(p);
            if (r == 0) cout << cost[q] << endl;
            else cout << time[q] << endl;
        }
    }
    return 0;
}

C++: #include <iostream>
#include <vector>
using namespace std;
struct edge {int from, to, cost;};
const int INF = 1000000;

void warshall_floyd(std::vector< std::vector<int> > & array, int V) {
  for(int k=0;k<V;k++)
   for(int i=0;i<V;i++)
    for(int j=0;j<V;j++)
     array[i][j] = std::min(array[i][j], array[i][k]+array[k][j]);
}
int main() {
  while(true) {
    int n, m;
    cin >> n >> m;
    if(n==0 && m==0) break;
    vector< vector<int> > cost(m, vector<int>(m, INF));
    vector< vector<int> > time(m, vector<int>(m, INF));
    for(int i=0;i<m;i++) {
      cost[i][i] = 0;
      time[i][i] = 0;
    }

    for(int i=0;i<n;i++) {
      int ai, bi, ci, ti;
      cin >> ai >> bi >> ci >> ti;
      ai--; bi--;
      cost[ai][bi] = ci;
      cost[bi][ai] = ci;
      time[ai][bi] = ti;
      time[bi][ai] = ti;
    }
    warshall_floyd(cost, m);
    warshall_floyd(time, m);


    int k;
    cin >> k;
    for(int i=0;i<k;i++) {
      int pi, qi, ri;
      cin >> pi >> qi >> ri;
      pi--;qi--;
      if(ri)
        cout << time[pi][qi] << endl;
      else
        cout << cost[pi][qi] << endl;
    }
  }
}