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]
					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 <cstdio>
#include <vector>
#include <queue>
#include <algorithm>

#define MAX_M 100
#define INF 1145141919

class edge{
public:
    int to;
    int cost;
    int time;
};

typedef std::pair<int, int> P;

int n, m, a, b, c, t, k, s, g, r;
int value[2][MAX_M + 1];
std::vector<edge> G[MAX_M + 1];


int ret(edge e){
    if(r == 0) return e.cost;
    return e.time;
}

void dij(){
    std::fill(value[r], value[r] + MAX_M + 1, INF);
    value[r][s] = 0;

    std::priority_queue<P, std::vector<P>, std::greater<P>> que;
    que.push(P(0, s));

    while(!que.empty()){
        P p = que.top(); que.pop();
        if(value[r][p.second] < p.first) continue;

        for(int i = 0; i < G[p.second].size(); i++){
            edge e = G[p.second][i];
            int u = ret(e);
            if(value[r][e.to] > value[r][p.second] + u){
                value[r][e.to] = value[r][p.second] + u;
                que.push(P(value[r][e.to], e.to));
            }
        }
    }

    printf("%d\n", value[r][g]);
}

int main(){

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

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


            edge e1, e2;
            e1.to   = b; e2.to = a;
            e1.cost = c; e2.cost = c;
            e1.time = t; e2.time = t;
            G[a].push_back(e1);
            G[b].push_back(e2);
        }


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

            dij();
        }
    }

    return 0;
}

C++: #include<iostream>

#define INF 1000000
using namespace std;

int main(){
	int data[2][110][110];
	for(int i=0;i<110;i++){
		for(int j=0;j<110;j++){
				data[1][i][j]=INF;
				data[0][i][j]=INF;
			
		}
	}	
	int n,m;
	while(cin>>n>>m && n|m){
	int a,b,cost,time;
	for(int i=0;i<n;i++){
		cin>>a>>b>>cost>>time;
		data[0][a][b]=cost;
		data[0][b][a]=cost;
		data[1][a][b]=time;
		data[1][b][a]=time;
	}

	for(int count=0;count<2;count++){
		for(int k=1;k<=m;k++){
			for(int i=1;i<=m;i++){
				for(int j=1;j<=m;j++)data[count][i][j]=min(data[count][i][j],data[count][i][k]+data[count][k][j]);
			}
		}
	}			

	int k;
	cin>>k;
	for(int i=0;i<k;i++){
		int p,q,r;
		cin>>p>>q>>r;
		cout<<data[r][p][q]<<endl;
	}
	}
}

C++: #include <bits/stdc++.h>
#define ll long long
#define rep(i,n) for(int i = 0; i < n; i++)
using namespace std;
using Graph = vector<vector<pair<int,int>>>;
int dij(int a,int b,Graph G){
  vector<ll>dist(G.size(),101640100165);
  dist[a] = 0;
  priority_queue<pair<int,int>,vector<pair<int,int>>,greater<pair<int,int>>>pq;
  pq.push({0,a});
  while(!(pq.empty())){
    int now = pq.top().second,now_cost = pq.top().first;
    pq.pop();
    for(auto i : G[now]){
      if(dist[i.first] <= now_cost + i.second)continue;
      dist[i.first] = now_cost + i.second;
      pq.push({dist[i.first],i.first});
    }
  }
  return dist[b];
}
int main(){
  while(true){
    int n,m;
    cin >> n >> m;
    if(n == 0 && m == 0)return 0;
    Graph cost(m),time(m);
    rep(i,n){
      int a,b;
      cin >> a >> b;
      a--,b--;
      int c,t;
      cin >> c >> t;
      cost[a].push_back({b,c});
      cost[b].push_back({a,c});
      time[a].push_back({b,t});
      time[b].push_back({a,t});
    }
    int cnt;
    cin >> cnt;
    rep(i,cnt){
      int a,b,c;
      cin >> a >> b >> c;
      a--,b--;
      if(c)cout << dij(a,b,time) << endl;
      else cout << dij(a,b,cost) << endl;
    }
  }
  return 0;
}

C++: #include <vector>
#include <iostream>
#include <utility>
#include <algorithm>
#include <string>
#include <deque>
#include <queue>
#include <tuple>
#include <queue>
#include <functional>
#include <cmath>
#include <iomanip>
#include <map>
#include <set>
#include <numeric>
#include <unordered_map>
#include <unordered_set>
#include <complex>
#include <iterator>
#include <array>
#include <memory>
#include <stack>
#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<n;i++)
#define all(in) in.begin(), in.end()
template<class T, class S> void cmin(T &a, const S &b) { if (a > b)a = b; }
template<class T, class S> void cmax(T &a, const S &b) { if (a < b)a = b; }
#define MAX 9999999
using namespace std;
typedef pair<int, int> pii;
typedef pair<double,double>pdd;
typedef pair<ll,ll>pll;
int main(){
    int n,m; cin>>n>>m;
    vector<vector<pii>>d(m+1,vector<pii>(m+1,pii(INF,INF)));
    rep(i,n){
        int a = 0,b = 0;pii hoge; cin>>a>>b>>hoge.first>>hoge.second;
        --a,--b;
        d[a][b]=hoge;
        d[b][a]=hoge;
    }
    rep(k,m)rep(j,m)rep(i,m)cmin(d[i][j].first,d[i][k].first+d[k][j].first);
    rep(k,m)rep(j,m)rep(i,m)cmin(d[i][j].second,d[i][k].second+d[k][j].second);
    int k; cin>>k;
    rep(i,k){
        int to,from,q; cin>>to>>from>>q;
        to--,from--;
        if(q)cout<<d[to][from].second<<endl;
        else cout<<d[to][from].first<<endl;
    }
    
}