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 <list>
#include <queue>
#include <vector>
#include <iostream>
#include <algorithm>
#include <functional>
#define INF (1LL << 60)
using namespace std;
bool used[100]; long long dist[100];
void dijkstra(int V, int E, int s, vector<pair<int, long long> > X[]) {
	priority_queue<pair<long long, int>, vector<pair<long long, int> >, greater<pair<long long, int> > > Q;
	for (int i = 0; i < V; i++) dist[i] = INF, used[i] = false;
	dist[s] = 0; Q.push(make_pair(0, s));
	int cnt = 0;
	while (!Q.empty()) {
		if (cnt > E) return; // NEGATIVE_CYCLE
		pair<long long, int> p = Q.top(); used[p.second] = true; Q.pop();
		for (int i = 0; i < X[p.second].size(); i++) {
			int to = X[p.second][i].first; long long leng = X[p.second][i].second;
			if (dist[to] > dist[p.second] + leng && !used[to]) {
				dist[to] = dist[p.second] + leng;
				Q.push(make_pair(dist[to], to));
			}
		}
	}
}
int n, m, q, a, b, c, u, v, w1, w2; vector<pair<int, long long> > G1[100], G2[100];
int main() {
	while(cin >> n >> m, n) {
		for(int i = 0; i < m; i++) G1[i].clear(), G2[i].clear();
		for(int i = 0; i < n; i++) {
			cin >> u >> v >> w1 >> w2;
			G1[u].push_back(make_pair(v, w1));
			G1[v].push_back(make_pair(u, w1));
			G2[u].push_back(make_pair(v, w2));
			G2[v].push_back(make_pair(u, w2));
		}
		cin >> q;
		for(int i = 0; i < q; i++) {
			cin >> a >> b >> c;
			if(c == 0) {
				dijksrta(m, n, a, G1);
				cout << dist[b] << endl;
			}
			else {
				dijkstra(m, n, a, G2);
				cout << dist[b] << endl;
			}
		}
	}
}

C++: // 2014/06/16 Tazoe

#include <iostream>
using namespace std;

const int INF = 1000000000;

int main()
{
	while(true){
		int n, m;
		cin >> n >> m;

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

		int C[100][100];
		int T[100][100];
		for(int i=0; i<m; i++){
			for(int j=0; j<m; j++){
				if(i==j){
					C[i][j] = T[i][j] = 0;
				}
				else{
					C[i][j] = T[i][j] = INF;
				}
			}
		}

		for(int i=0; i<n; i++){
			int a, b, c, t;
			cin >> a >> b >> c >> t;

			C[a-1][b-1] = C[b-1][a-1] = c;
			T[a-1][b-1] = T[b-1][a-1] = t;
		}
    for(int k=0;k<n;k++){
      for(int i=0;i<n;i++){
        for(int j=0;j<n;j++){
          if(C[i][j] > C[i][k]+C[k][j])
            C[i][j] = C[i][k] + C[k][j];
          if(T[i][j] > T[i][k]+T[k][j])
            T[i][j] = T[i][k] + T[k][j];
        }
      }
    }
    unsigned int k;
    cin >> k;
    for(int i=0;i<k;i++){
      int p,q,r;
      cin >> p >> q;
      if(k == 0  &&  q == 0)
        return 0;
      cin >> r;

      if(r==0){
        cout << C[p][q] << endl;
      } else {
        cout << T[p][q] << endl;
      }
    }
    break;
	}

	return 0;
}

C++: #include<iostream>
#include<vector>
#include<algorithm>
#define N 100
#define M 1000

using namespace std;

int Dijkstra(vector< vector<int> > data, int s, int g){
  vector<bool> is_reached(data.size(), false);
  vector<int> ans(data.size(), M);
  ans[s] = 0;

  int i, j;
  i = s;
  while(i != g){
    is_reached[i] = true;
    for(j=0; j<data[i].size(); ++j){
      ans[j] = min(ans[j], ans[i] + data[i][j]);
    }
    for(i=-1, j=0; j<is_reached.size(); ++j){
      if(!is_reached[j] && (i < 0 || ans[i] > ans[j])) i = j;
    }
  }
  return ans[g];
}

int main(){
  int n, m, a, b, c, t;
  int p, q, r;

  while(1){
    cin >> n >> m;
    if(n == 0 && m == 0) break;
    vector< vector<int> > cost(m, vector<int>(m, M));
    vector< vector<int> > time(m, vector<int>(m, M));

    for(int i=0; i<n; ++i){
      cin >> a >> b >> c >> t;
      --a;
      --b;
      cost[a][b] = c;
      cost[b][a] = c;
      time[a][b] = t;
      time[b][a] = t;
    }
    cin >> n;
    for(int i=0; i<n; ++i){
      cin >> p >> q >> r;
      --p;
      --q;
      if(r == 0) cout << Dijkstra(cost, p, q) << endl;
      else cout << Dijkstra(time, p, q) << endl;
    }
  }
  return 0;
}

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

using namespace std;

int cost[100][100];

int main()
{
	for(;;){
		int t,tt,ttt,tttt;
		int time[100][100];
		
		//n:f[^Ì m:wÌ
		int n, m;
		
		//k:â¢í¹Ì
		int k;
		
		cin >> n >> m;
		
		if(n == 0 && m == 0){
			break;
		}
		
		for(int i = 0; i < 100; i++){
			for(int j = 0; j < 100; j++){
				if(i!=j)
				{
					time[i][j] = 10000000;
					cost[i][j] = 10000000;
				}
				else{
					cost[i][j]=time[i][j]=0;
				}
			}
		}
		
		for(int i = 0; i < n; i++){
			cin >> t >> tt >> ttt >> tttt;
			t--;
			tt--;
			cost[t][tt]=ttt;
			time[t][tt]=tttt;
			cost[tt][t]=ttt;
			time[tt][t]=tttt;
		}
		
		cin >> k;
		
		for(int i = 0; i < k; i++){
			cin >> t >> tt >> ttt;
			
			for(int f = 0; f < m; f++){
				for(int fd = 0; fd < m; fd++){
					for(int fds = 0; fds < m; fds++){
							cost[fd][fds] = min(cost[fd][fds] , cost[fd][f] + cost[f][fds]);
							time[fd][fds] = min(time[fd][fds] , time[fd][f] + time[f][fds]);
					}
				}
			}
			if(ttt == 0){
				cout << cost[t-1][tt-1] << endl;
			}
			else{
				cout << time[t-1][tt-1] << endl;
			}
		}
	}
	
}