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<queue>
#include<algorithm>
#include<utility>
#include<vector>
#include<climits>
using namespace std;

#define MAX_M 110

struct edge{int to,cost;};
typedef pair<int,int> P;

vector<edge> c[2][MAX_M];

int dijkstra(int s,int e,bool r){
	bool use[MAX_M];
	for(int i=0;i<MAX_M;i++){
		use[i]=0;
	}
	priority_queue<P,vector<P>,greater< P > > que;
	
	que.push(P(0,s));
	int ans;
	while(!que.empty()){
		P p=que.top();que.pop();
		//cout<<"pop "<<p.second<<" "<<p.first<<endl;
		int v=p.second;
		if(v==e){
			ans=p.first;
			break;
		}
		
		if(use[v]) continue;
		use[v]=1;
		//cout<<"use "<<p.second<<" "<<p.first<<endl;
		for(int i=0;i<c[r][v].size();i++){
			edge e=c[r][v][i];
			//if(!use[e.to]){
				que.push(P(p.first+e.cost,e.to));
			//}
		}
	}
	
	return ans;
}

int main(){
	int n,m;
	while(cin>>n>>m,n!=0||m!=0){
		for(int r=0;r<2;r++){
			for(int i=0;i<MAX_M;i++){
				c[r][i].clear();
			}
		}
		for(int i=0;i<n;i++){
			int a,b,cos,tim;
			cin>>a>>b>>cos>>tim;
			edge co,t;
			co.to=b;co.cost=cos;
			t.to=b;t.cost=tim;
			c[0][a].push_back(co);
			c[1][a].push_back(t);
			co.to=a;t.to=a;
			c[0][b].push_back(co);
			c[1][b].push_back(t);
		}
		int k;
		cin>>k;
		for(int i=0;i<k;i++){
			int s,e;
			bool r;
			cin>>s>>e>>r;
			int ans=dijkstra(s,e,r);
			cout<<ans<<endl;
		}
	}
}

C++: #include<iostream>
#include<string.h>
#include<vector>
#include<list>
#include<stdio.h>
#include<math.h>
#include<iomanip>
#include<map>
#include<stack>
#include<queue>
#define range(i,a,b) for(int i = (a); i < (b); i++)
#define rep(i,b) range(i,0,b)
#define debug(x) cout << "debug " << x << endl;
using namespace std;

int dp[105][105][2], n, m;

int main(){
    int l;
    int a, b, c, d;
    int st, en, de;

    while(cin >> n >> m, n||m){
        rep(i, 105){
            rep(j, 105){
                rep(k, 2){
                    dp[i][j][k] = 2 << 24;
                }
            }
        }

        rep(i, n){
            cin >> a >> b >> c >> d;
            dp[a][b][0] = dp[b][a][0] = c;
            dp[a][b][1] = dp[b][a][1] = d;
        }

        rep(k, m+1){
            rep(i, m+1){
                rep(j, m+1){
                    dp[i][j][0] = min(dp[i][k][0] + dp[k][j][0], dp[i][j][0]);
                    dp[i][j][1] = min(dp[i][k][1] + dp[k][j][1], dp[i][j][1]);
                }
            }
        }

        cin >> l;
        rep(i, l){
            cin >> st >> en >> de;
            cout << dp[st][en][de] << endl;
        }
    }
}

C++: #include<iostream>
#include<cstring>
#include<algorithm>
using namespace std;
int x[1000][1000][2], n, m, a, b, c, d, q, e;

int path(int n, int s, int g) {
	int p[1000];
	memset(p, 127, sizeof(p));
	p[s] = 0;
	e = min(n, 9);
	for (int i = 0; i < e; i++){
		for (int j = 1; j <= n; j++) {
			for (int k = 1; k <= n; k++) {
				if (x[j][k][1] < 10000000) {
					p[k] = min(p[k], p[j] + x[j][k][1]);
				}
			}
		}
	}
	return p[g];
}

int score(int n, int s, int g) {
	int p[1000];
	memset(p, 127, sizeof(p));
	p[s] = 0;
	e = min(n, 9);
	for (int i = 0; i < e; i++) {
		for (int j = 1; j <= n; j++) {
			for (int k = 1; k <= n; k++) {
				if (x[j][k][0] < 10000000) {
					p[k] = min(p[k], p[j] + x[j][k][0]);
				}
			}
		}
	}
	return p[g];
}

int main() {
	while (true) {
		memset(x, 127, sizeof(x));
		cin >> m >> n;
		if (m == 0 && n == 0) { break; }
		for (int i = 0; i < m; i++) {
			cin >> a >> b >> c >> d;
			x[a][b][0] = c;
			x[b][a][0] = c;
			x[a][b][1] = d;
			x[b][a][1] = d;
		}
		cin >> q;
		for (int i = 0; i < q; i++) {
			cin >> a >> b >> c;
			if (c == 0) { cout << score(n, a, b) << endl; }
			else { cout << path(n, a, b) << endl; }
		}
	}
}

C++: #include <bits/stdc++.h>

const int MOD = 1e9 + 7;
const int iINF = 1000000000;
const long long int llINF = 1000000000000000000;
const double PI = acos(-1.0);
#define rep(i, n) for (int i = 0; i < (n); i++)

using namespace std;
using ll = long long int;
using P = pair<int, int>;
using edge = struct
{
    int to;
    int cost;
};

int dx[4] = {1, 0, -1, 0};
int dy[4] = {0, 1, 0, -1};

int costs[100][100];
int times[100][100];

void Warshall_Floyd(int N, int (&cost)[100][100])
{
    rep(k, N) rep(i, N) rep(j, N)
        cost[i][j] = min(cost[i][j], cost[i][k] + cost[k][j]);
}

int main()
{
    int N, M;
    while (cin >> N >> M && N)
    {
        rep(i, 100) rep(j, 100) costs[i][j] = iINF;
        rep(i, 100) rep(j, 100) times[i][j] = iINF;

        rep(i, N)
        {
            int a, b, c, t;
            cin >> a >> b >> c >> t;
            a--;
            b--;

            costs[a][b] = min(costs[a][b], c);
            costs[b][a] = min(costs[b][a], c);

            times[a][b] = min(times[a][b], t);
            times[b][a] = min(times[b][a], t);
        }

        Warshall_Floyd(N, costs);
        Warshall_Floyd(N, times);

        int K;
        cin >> K;

        int p, q, r;

        rep(i, K)
        {
            cin >> p >> q >> r;
            p--;
            q--;

            cout << (r == 1 ? times[p][q] : costs[p][q]) << endl;
        }
    }
    
    return 0;
}