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]
					t_newlen := t_dist[i][k] + t_dist[k][j]
					if c_newlen < c_dist[i][j] {
						c_dist[i][j] = c_newlen
						c_prev[i][j] = c_prev[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 100000000
using namespace std;
int main(){
  int n,m;
  while(cin>>n>>m){
    if(n==0&&m==0) break;
    int d0[m+1][m+1],d1[m+1][m+1];
    for(int i=1;i<=m;i++){
      for(int j=1;j<=m;j++){
    d0[i][j] = INF;
    d1[i][j] = INF;
      }
    }
    int a,b,cost,time;
    for(int i=0;i<n;i++){
      cin >> a >> b >> cost >> time;
      d0[a][b] = d0[b][a] = cost;
      d1[a][b] = d1[b][a] = time;
    }
    for(int i=1;i<=m;i++){
      for(int j=1;j<=m;j++){
    for(int k=1;k<=m;k++){
      d0[j][k] = min(d0[j][k],d0[j][i]+d0[i][k]);
      d1[j][k] = min(d1[j][k],d1[j][i]+d1[i][k]);
    }
      }
    }
    int s,p,q,r;
    cin >> s;
    for(int i=0;i<s;i++){
      cin >> p >> q >> r;
      if(p==q) cout << 0 << endl;
      else if(r==0) cout << d0[p][q] << endl;
      else cout << d1[p][q] << endl;
    }
  }
  return 0;
}

C++: #include <iostream>
#include <vector>
#include <cmath>

#define INF 100000000

using namespace std;

int main()
{
    int n, m;
    while(true) {
        cin >> n >> m;
        if(n == 0 || m == 0) break;
        int times[n+1][n+1], costs[n+1][n+1];
        int a,b,cost,time;
        for(int i = 1; i <= n; i++) 
            for(int j = 1; j <= n; j++) 
                times[i][j] = costs[i][j] = (i==j) ? 0 : INF; 
        
        for(int i = 0; i < n; i++) {
            cin >> a >> b >> cost >> time;
            costs[a][b] = costs[b][a] = cost;
            times[a][b] = times[b][a] = time;
        }

        for(int a = 1; a <= n; a++) {
            for(int b = 1; b <= n; b++) {
                for(int c = 1; c <= n; c++) {
                    times[a][b] = min(times[a][b], times[a][c] + times[c][b]);
                    costs[a][b] = min(costs[a][b], costs[a][c] + costs[c][b]);
                }
            }
        }

        int p,q,r,qn;
        cin >> qn;
        for(int i = 0; i < qn; i++) {
            cin >> p >> q >> r;
            if(r == 1) cout << times[p][q] << endl;
            else       cout << costs[p][q] << endl;
        }
    }
    return 0;
}

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

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 <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>

using namespace std;

#define all(c) c.begin(),c.end()
#define rall(c) c.rbegin(),c.rend()
#define rep(i,n) for(int i=0;i<(n);i++)
#define tr(it,container) for(typeof(container.begin()) it = container.begin(); \
                                                  it != container.end(); ++it)
#define mp(a,b) make_pair((a),(b))
#define eq ==

typedef long long ll;
typedef complex<double> point;
typedef pair<int,int> pii;

// →↑←↓
const int dx[] = {1,0,-1,0};
const int dy[] = {0,-1,0,1};


const double EPS = 1e-9;

struct Edge{
    int from,to,cost,time;
    Edge(int from,int to,int cost,int time)
        : from(from),to(to),cost(cost),time(time) {};
};

int main(){
    int n,m;
    cin >> n >> m;
    vector<vector<Edge> > V(m);

    for(int i=0;i<n;i++){
        int a,b,cost,time;
        cin >> a >> b >> cost >> time;
        a--;b--;
        V[a].push_back(Edge(a,b,cost,time));
        V[b].push_back(Edge(b,a,cost,time));
    }
    int k;
    cin >> k;
    for(int i=0;i<k;i++){
        int p,q,r;
        cin >> p >> q >> r;
        p--,q--;
        vector<char> visited(m,false);
        //                 cost,where
        priority_queue<pair<int,int> ,vector<pair<int,int> >, greater<pair<int,int> > > Q;
        Q.push(make_pair(0,p));
        while(!Q.empty()){
            int cost,where;
            cost = Q.top().first;
            where = Q.top().second;
            Q.pop();
            if(visited[where]) continue;
            if(where == q){
                cout << cost << endl;
                break;
            }
            visited[where] = true;
            for(int j=0;j<(int)V[where].size();j++){
                if(r == 0){
                    Q.push(make_pair(V[where][j].cost+cost,V[where][j].to));
                }else{
                    Q.push(make_pair(V[where][j].time+cost,V[where][j].to));
                }
            }
        }
    }
    return 0;
}