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
			c_matrix[b-1][a-1] = c
			t_matrix[a-1][b-1] = t
			t_matrix[b-1][a-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 <string>
#include <vector>
#include <algorithm>
#include <cmath>
#include <cstdio>
#include <functional>
#include <numeric>
#include <stack>
#include <queue>
#include <map>
#include <set>
#include <utility>
#include <sstream>
#include <complex>

using namespace std;

#define FOR(i,a,b) for(long long i=(a);i<(b);i++)
#define REP(i,N) for(long long i=0;i<(N);i++)
#define ALL(s) (s).begin(),(s).end()
#define fi first
#define se second

#define PI acos(-1.0)
#define INF 1000000007

typedef long long ll;
typedef pair<ll, ll> P;
typedef pair<double, double> PD;
typedef pair<string, ll> PS;
typedef vector<ll> V;

struct edge{
	ll to, cost, time;
	edge(ll _to, ll _cost, ll _time) :to(_to), cost(_cost), time(_time){};
};

ll n, m, a, b, cost, time, k, s, g, f;

ll mincost[1000], mintime[1000];
vector<edge> G[1000];

void dijkstra0(ll start){
	fill(mincost, mincost + 1000, INF);
	mincost[start] = 0;
	priority_queue<P> que;
	que.push(P(0, start));

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

		for (int i = 0; i < G[v].size(); i++){
			edge e = G[v][i];
			if (mincost[e.to] > mincost[v] + e.cost){
				mincost[e.to] = mincost[v] + e.cost;
				que.push(P(mincost[e.to], e.to));
			}
		}
	}
}

void dijkstra1(ll start){
	fill(mintime, mintime + 1000, INF);
	mintime[start] = 0;
	priority_queue<P> que;
	que.push(P(0, start));

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

		for (int i = 0; i < G[v].size(); i++){
			edge e = G[v][i];
			if (mintime[e.to] > mintime[v] + e.time){
				mintime[e.to] = mintime[v] + e.time;
				que.push(P(mintime[e.to], e.to));
			}
		}
	}
}

int main(){
	while (cin >> n >> m&&n + m){
		REP(i, n){
			cin >> a >> b >> cost >> time;
			G[a].push_back(edge(b, cost, time));
			G[b].push_back(edge(a, cost, time));
		}
		cin >> k;
		REP(i, k){
			cin >> s >> g >> f;
			if (f == 0){
				dijkstra0(s);
				cout << mincost[g] << endl;
			}
			else{
				dijkstra1(s);
				cout << mintime[g] << endl;
			}
		}
	}
}

C++: #include<iostream>
#include<algorithm>
using namespace std;
const int INF = 111111111;
int main(void){
  int n,m,a,b,cost,time,l,p,q,r;
  int c[105][105],t[105][105];
  for( ; ; ){
    cin >> m >> n;
    if(!m && !n) break;

    for(int i = 1;i <= n; i++){
      for(int j = 1;j <= n; j++){
	if(i == j) c[i][j] = t[i][j] = 0;
	else c[i][j] = t[i][j] = INF;
      }
    }

    for(int i = 0;i < m; i++){
      cin >> a >> b >> cost >> time;
      c[a][b] = c[b][a] = cost;
      t[a][b] = t[b][a] = time;
    }

    for(int k = 1;k <= n; k++)
      for(int i = 1;i <= n; i++)
	for(int j = 1;j <= n; j++) c[i][j] = min(c[i][j], c[i][k] + c[k][j]);

    for(int k = 1;k <= n; k++)
      for(int i = 1;i <= n; i++)
	for(int j = 1;j <= n; j++) t[i][j] = min(t[i][j], t[i][k] + t[k][j]);

    cin >> l;
    for(int i = 0;i < l; i++){
      cin >> p >> q >> r;
      cout << (r ? t[p][q] : c[p][q]) << endl;
    }
  }
}

C++: #include<bits/stdc++.h>
using namespace std;

typedef long long int ll;
typedef pair<int, int> pii;
typedef vector<int> vi;
typedef vector<pair<int, int> > vii;
#define rrep(i, m, n) for(int (i)=(m); (i)<(n);  (i)++)
#define  rep(i, n)    for(int (i)=0; (i)<(n);  (i)++)
#define  rev(i, n)    for(int (i)=(n)-1; (i)>=0; (i)--)
#define vrep(i, c)    for(__typeof((c).begin())i=(c).begin(); i!=(c).end(); i++)
#define  ALL(v)       (v).begin(), (v).end()
#define mp            make_pair
#define pb            push_back
template<class T1, class T2> inline void minup(T1& m, T2 x){ if(m>x) m=static_cast<T2>(x); }
template<class T1, class T2> inline void maxup(T1& m, T2 x){ if(m<x) m=static_cast<T2>(x); }

#define INF 1000000000LL
#define MOD 1000000009
#define EPS 1E-9

const int MAX_V = 1000;
ll dp[2][MAX_V][MAX_V];
int E, V;
int a, b;
ll c, t;
int k;
int p, q, r;

int main()
{
  while((cin >> E >> V) && E && V){
    rep(i, V) rep(j, V) dp[0][i][j] = dp[1][i][j] = INF;

    rep(i, E){
      cin >> a >> b >> c >> t;
      a-=1;  b-=1;
      dp[0][a][b] = dp[0][b][a] = c;
      dp[1][a][b] = dp[0][b][a] = t;
    }

    rep(b, 2) rep(k, V) rep(i, V) rep(j, V) minup(dp[b][i][j], dp[b][i][k] + dp[b][k][j]);

    cin >> k;
    while(k--){
      cin >> p >> q >> r;
      cout << dp[r][p-1][q-1] << endl;
    }
  }

  return 0;
}

C++: #include <cstdio>
#include <vector>

using namespace std;

class Edge{
public:
	int from,to,cost,time;
	void Swap(){
		int self = from;
		from = to;
		to = from;
	}
	int GetValue(int r){
		if(r == 0){
			return cost;
		}else{
			return time;
		}
	}
};

vector<Edge> edge;
int n,m;

const int INF = 100000000;

int solve(const int p,const int q,const int r);

int main(){
	scanf("%d %d",&n,&m);
	for(int i=0;i<n;i++){
		Edge ed;
		scanf("%d %d %d %d",&ed.from,&ed.to,&ed.cost,&ed.time);
		edge.push_back(ed);
		ed.Swap();
		edge.push_back(ed);
	}
	int k;
	int p,q,r;
	scanf("%d",&k);
	for(int i=0;scanf("%d %d",&p,&q) && p && q && i < k;i++){
		scanf("%d",&r);
		printf("%d\n",solve(p,q,r));
	}
	return 0;
}

int solve(const int p,const int q,const int r){
	vector<int> d(m+1);
	for(int i=0;i<=m;i++){
		d[i] = INF;
	}
	d[p] = 0;
	
	bool flag;
	while(1){
		flag = false;
		vector<Edge>::iterator it;
		for(it = edge.begin();it != edge.end();it++){
			if(d[(*it).from] != INF && d[(*it).to] > d[(*it).from] + (*it).GetValue(r)){
				d[(*it).to] = d[(*it).from] + (*it).GetValue(r);
				flag = true;
			}
		}
		if(!flag){
			break;
		}
	}
	
	return d[q];
}