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 <iostream>
#include <vector>
#include <string.h>
#include <time.h>

using namespace std;

static const int TYPE_COST =0;
static const int TYPE_TIME =1;

class station{
public:
	int cost;
	bool visited;
	vector<int> edge_to;
	vector<int> edge_cost;
	vector<int> edge_time;
	
	 public:
		station() :  cost(-1), visited(false){}
		void add_to(int to, int cost, int time)
		{
			this->edge_to.push_back(to);
			this->edge_cost.push_back(cost);
			this->edge_time.push_back(time);
		}
};

int dijkstra(station* sta, int size, int from, int to, int type);
void reset(station* sta, int size);

int main(int argc, char** argv)
{
	while( 1 ){
		int n, m, from, to, cost, time, type;
		cin >> n;
		cin >> m;
		if(n==0 && m==0) break;
		
		station sta[m];
		for(int i=0; i<m; i++){
			sta[i] = station();
		}
		
		for(int i=0; i<n; i++){
			cin >> from;
			cin >> to;
			cin >> cost;
			cin >> time;
			sta[from-1].add_to(to-1, cost, time);
			sta[to-1].add_to(from-1, cost, time);
		}
		cin >> n;
		for(int i=0; i<n; i++){
			cin >> from;
			cin >> to;
			cin >> type;
			clock_t t1 = clock();
			cout << dijkstra(sta, m, from-1, to-1, type) << endl;
			clock_t t2 = clock();
			cout << "Time : "  << t2 - t1<< " (msec)" << endl;
			reset(sta, m);
		}
	}
	
	return 0;
}

int dijkstra(station* sta, int size, int start, int goal, int type)
{
	int to, cost;
	station done;
	vector<station> q;
	sta[start].cost = 0;
	q.push_back(sta[start]);
	
	while(!q.empty()){
		done = q[0];
		q.erase(q.begin());
		done.visited = true;
		
		for(int i=0; i<done.edge_to.size(); i++){
			to = done.edge_to[i];
			if(type==TYPE_COST) cost = done.cost + done.edge_cost[i];
			if(type==TYPE_TIME) cost = done.cost + done.edge_time[i];
			if(sta[to].cost < 0 || cost < sta[to].cost){
				sta[to].cost = cost;
				q.push_back(sta[to]);
			}
		}
	}
	
	return sta[goal].cost;
}

void reset(station* sta, int size)
{
	for(int i=0; i<size; i++){
		sta[i].visited = false;
		sta[i].cost = -1;
	}
}

C++: #include<iostream>
#include<string>
#include<cstdio>
#include<algorithm>
#include<stack>
#include<queue>
#include<vector>
#include<cmath>
#include<utility>
#include<set>
#include<complex>
#include<map>
#define vi vector<int>
#define vvi vector<vector<int> >
#define ll long long int
#define vl vector<ll>
#define vvl vector<vector<ll>>
#define vb vector<bool>
#define vc vector<char>
#define vs vector<string>
#define ld long double
#define INF 1e9
#define EPS 0.0000000001
#define rep(i,n) for(int i=0;i<n;i++)
#define loop(i,s,n) for(int i=s;i<s;i++)
#define CC puts("-------ok--------");
#define all(in) in.begin(), in.end()
using namespace std;
typedef pair<int,int> pii;
#define MAX 99999999
signed main(){
while(1){
	int n,m;
	cin>>n>>m;
    if(!(n+m))break;
	vector<vector<pii>>v(n+1,vector<pii>(n+1,pii(INF,INF)));
	rep(i,n+1)v[i][i]=pii(INF,INF);
	rep(i,n){
		pii temp;
		int s,g;
		cin>>s>>g>>temp.first>>temp.second;
        v[--s][--g]=temp;
	}
    rep(k,m){
        rep(i,m){
            rep(j,m){
                v[i][j].first=min(v[i][k].first+v[k][j].first,v[i][j].first);
                v[i][j].second=min(v[i][k].second+v[k][j].second,v[i][j].second);

            }
        }
    }
    int k; cin>>k;
    rep(i,k){
        int s,g,r; cin>>s>>g>>r;
        if(!r)cout<<v[--s][--g].first<<endl;
        else cout<<v[--s][--g].second<<endl;
    }
    
    }
}

C++: #include<iostream>
#include<algorithm>
#include<cstring>
#define INF 111111111
using namespace std;

int n,m;
int a,b,c,d,cost[1000][1000],tim[1000][1000];
int memo[1000];
int ans[1000],ans2[1000];
int p,q,r;
int k,x,y,z;

void cost_a(){
  ans[x] = 0;

  while(true){
    int s = -1;

    for(int i=1;i<=m;i++){
      if(!memo[i] && (s == -1 || ans[i] < ans[s])) s = i;
    }

    if(s == -1) break;
    memo[s] = 1;

    for(int i=1;i<=m;i++) ans[i] = min(ans[i],ans[s] + cost[i][s]);
  }
}

void time_a(){
  ans2[x] = 0;

  while(true){
    int s = -1;

    for(int i=1;i<=m;i++){
      if(!memo[i] && (s == -1 || ans[i] < ans2[s])) s = i;
    }

    if(s == -1) break;
    memo[s] = 1;

    for(int i=1;i<=m;i++) ans2[i] = min(ans2[i],ans2[s] + tim[i][s]);
  }
}

int main(){

  while(true){
    cin >> n >> m;
    if(!n && !m) break;

    for(int i=0;i<1000;i++){
      for(int j=0;j<1000;j++) cost[i][j] = tim[i][j] = INF;
      ans[i] = ans2[i] = INF;
    }

    for(int i=0;i<n;i++){
      cin >> a >> b >> c >> d;
     
      if(cost[a][b] > c) cost[a][b] = cost[b][a] = c;
      if(tim[a][b] > d) tim[a][b] = tim[b][a] = d;

    }

    cin >> k;

    for(int i=0;i<k;i++){
      cin >> x >> y >> z;

      memset(memo,0,sizeof(memo));

      if(!z){
	cost_a();
	cout << ans[y] << endl;
      }

      else{
	time_a();
	cout << ans2[y] << endl;
      }
    }
  }
}