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>

#define INF 1001;
using namespace std;


int main(){
  int n,m;
  while(1){
    cin>>n>>m;
    if(!n&&!m)break;
    int s_tim[m][m];
    int c_money[m][m];
    int a,b,cost,tim;

    for(int i=0;i<m;i++){
      for(int j=0;j<n;j++){
        s_tim[i][j]=INF;
        c_money[i][j]=INF;
      }
    }
    for(int i=0;i<m;i++){
      s_tim[i][i]=0;
      c_money[i][i]=0;
    }
    for(int i=0;i<n;i++){
      cin>>a>>b>>cost>>tim;
      s_tim[a-1][b-1]=tim;s_tim[b-1][a-1]=tim;
      c_money[a-1][b-1]=cost;c_money[b-1][a-1]=cost;
    }

    for(int k=0;k<m;k++){
      for(int i=0;i<m;i++){
        for(int j=0;j<m;j++){
          if(s_tim[i][j]>s_tim[i][k]+s_tim[k][j]){
            s_tim[i][j]=s_tim[i][k]+s_tim[k][j];
          }
          if(c_money[i][j]>c_money[i][k]+c_money[k][j]){
            c_money[i][j]=c_money[i][k]+c_money[k][j];
          }
        }
      }
    }

    int contacts,p,q,r;
    cin>>contacts;

    for(int i=0;i<contacts;i++){
      cin>>p>>q>>r;
      if(r){cout<<s_tim[p-1][q-1];}
      else{ cout<<c_money[p-1][q-1];}
      cout<<endl;
    }
  }
}

C++: #include <iostream>
#include <cstdio>
#include <iomanip>
#include <vector>
#include <map>
#include <set>
#include <queue>
#include <bitset>
#include <stack>
#include <utility>
#include <numeric>
#include <algorithm>
#include <functional>
#include <cctype>
#include <complex>
#include <string>
#include <sstream>
#include <cassert>
using namespace std;

//common
typedef int  i32;
typedef long long i64,ll;
#define BR "\n"

#define ALL(c) (c).begin(),(c).end()
#define REP(i,n) for(int i=0;i<(int)(n);++i)
#define EACH(it,o) for(auto it = (o).begin(); it != (o).end(); ++it)
#define IN(l,v,r) ((l)<=(v) && (v)<(r))

typedef vector<int> vi; typedef pair<int,int> pii; typedef vector<pair<int,int> > vpii;
typedef long long ll; typedef vector<long long> vl; typedef pair<long long,long long> pll; typedef vector<pair<long long,long long> > vpll;
typedef vector<string> vs; typedef long double ld;

//config
#define MODE_DEBUG
//#define INF 1<<30
//#define EPS 1e-8
//const ll MOD =100000007;

//debug
#ifdef MODE_DEBUG
#define LINE()    cerr<< " (L" << __LINE__ << ")"
#define LINELN()    LINE()<<endl

#define  DUMP(x)  cerr << #x << " = " << (x) <<endl
#define DEBUG(x) DUMP(x) << " (L" << __LINE__ << ")" << " " << __FILE__<<endl
#define CHECK(exp,act)  if(exp!=act){DUMP(exp);DEBUG(act);}
#define STOP(e)  CHECK(e,true);if(!(e)) exit(1);
#else
#define DUMP(x)
#define DEBUG(x)
#define CHECK(exp,act)
#define STOP(e)
#endif

template<class T> inline string toString(const vector<T>& x) {
	stringstream ss;
	REP(i,x.size()){
		if(i!=0)ss<<" ";
		ss<< x[i];
	}
	return ss.str();
}
template<class T> inline string toString(const vector<vector<T>>& map) {
	stringstream ss;
	REP(i,map.size()){
		if(i!=0)ss<<BR;
		ss<< toString(map[i]);
	}
	return ss.str();
}
template<class K,class V>  string toString(map<K,V>& x) {
	string res;stringstream ss;
	for(auto& p:x)ss<< p.first<<":" << p.second<<" ";
	return ss.str();
}

template<typename T,typename V> inline T mod(T v,V MOD){
	return (v%MOD+MOD)%MOD;
}

using Mat=vector<vector<int>>;
void warshall_floyd(Mat& d){
    const int V=d.size();
    for(int k=0;k<V;k++)
        for(int i=0;i<V;i++)for(int j=0;j<V;j++)
            if(d[i][j]>d[i][k] + d[k][j]){
                d[i][j]=d[i][k] + d[k][j];
                //prev[i][j]=k;
            }
}

const int INF =1<<28;
int main(){
	int N,M;cin >> N >> M;
	Mat ds(M+1,vector<int>(M+1,INF));
	Mat cs(M+1,vector<int>(M+1,INF));
	REP(i,M+1)ds[i][i]=cs[i][i]=0;

	REP(i,N){
		int a,b,c,t; cin >> a >> b >> c>>t;
		ds[a][b]=min(ds[a][b],t);ds[b][a]=min(ds[b][a],t);

		cs[a][b]=min(cs[a][b],c);cs[b][a]=min(cs[b][a],c);
	}
	warshall_floyd(ds);DUMP(toString(ds));
	warshall_floyd(cs);DUMP(toString(cs));
	int k;cin >> k;
	REP(i,k){
		int p,q,r;cin >> p >> q >>r;
		if(r==0)cout<<cs[p][q]<<endl;
		else cout<<ds[p][q]<<endl; 
	}
	return 0;
}

C++: #include "bits/stdc++.h"
using namespace std;
typedef long long ll;
typedef pair<int,int> pii;
#define rep(i,n) for(ll i=0;i<(ll)(n);i++)
#define all(a)  (a).begin(),(a).end()
#define pb push_back
#define INF 999999999
#define MAX_V 100

struct edge{int to,cost;};
vector<edge> G[2][MAX_V];
int d[2][MAX_V];

int dijkstra(int s,int V,int ver){
    priority_queue< pii,vector<pii>,greater<pii> > que;
    rep(i,MAX_V)d[ver][i]=INF;
    d[ver][s]=0;
    que.push(pii(0,s));
    
    while(que.size()){
        pii p=que.top();
        que.pop();
        
        int v=p.second;
        if(d[ver][v]<p.first)continue;
        
        rep(i,G[ver][v].size()){
            edge e=G[ver][v][i];
            if(d[ver][e.to]>d[ver][v]+e.cost){
                d[ver][e.to]=d[ver][v]+e.cost;
                que.push(pii(d[ver][e.to],e.to));
            }
        }
    }
    return d[ver][V];
}




int main(){
    int n,m;
    while(cin>>n>>m){
        if(n==0&&m==0)break;
        rep(i,2)rep(j,MAX_V)G[i][j].clear();
        rep(i,n){
            int a,b,cost,time;
            cin>>a>>b>>cost>>time;
            a--,b--;
            G[0][a].pb(edge{b,cost});
            G[0][b].pb(edge{a,cost});
            G[1][a].pb(edge{b,time});
            G[1][b].pb(edge{a,time});
        }
        int k;
        cin>>k;
        rep(i,k){
            int p,q,r;
            cin>>p>>q>>r;
            p--,q--;
            cout<<dijkstra(p,q,r)<<endl;
        }
    }
}