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<bits/stdc++.h>
using namespace std;
#define INF 1e7
struct edge{int to,cost,time;};
vector<edge> G[101];
int d[101];
bool visited[101];
void dic(int p,int m){
  for(int i=0;i<101;++i) d[i]=INF,visited[i]=false;
  d[p]=0;
  int id;
  for(int i=0;i<m;++i){
    id=-1;
    for(int j=0;j<m;++j){
      if(!visited[j])
        if(id==-1||d[id]>d[j])
          id=j;
    }
    visited[id]=true;
    for(int i=0;i<G[id].size();++i){
      edge e = G[id][i];
      d[e.to]=min(d[e.to],d[id]+e.cost);
    }
  }
}
void dit(int p,int m){
  for(int i=0;i<101;++i) d[i]=INF,visited[i]=false;
  d[p]=0;
  int id;
  for(int i=0;i<m;++i){
    id=-1;
    for(int j=0;j<m;++j){
      if(!visited[j])
        if(id==-1||d[id]>d[j])
          id=j;
    }
    visited[id]=true;
    for(int i=0;i<G[id].size();++i){
      edge e = G[id][i];
      d[e.to]=min(d[e.to],d[id]+e.time);
    }
  }
}
int main(){
  int n,m;
  while(cin>>n>>m,n){
    for(int i=0;i<101;++i) G[i].clear();
    for(int i=0;i<n;++i){
      int a,b,c,t; cin>>a>>b>>c>>t;
      G[a].push_back((edge){b,c,t});
      G[b].push_back((edge){a,c,t});
    }
    int k; cin>>k;
    for(int i=0;i<k;++i){
      int p,q,r; cin>>p>>q>>r;
      if(r) dit(p,m);
      else dic(p,m);
      cout<<d[q]<<endl;
    }
  }
  return 0;
}

C++: #include <vector>
#include <map>
#include <stack>
#include <queue>
#include <cstring>
#include <string>
#include <sstream>
#include <algorithm>
#include <iomanip>
#include <iostream>

#define VARIABLE(x) cerr << #x << "=" << x << endl
#define rep(i,n) for(int i=0;i<(int)(n);i++)
#define REP(i,m,n) for (int i=m;i<(int)(n);i++)

const int INF = 10000000;
using namespace std;
typedef long long  ll;
const int MAX = 10000;

/** Problem0200 : Traveling Alone : One-way Ticket of Youth **/
int costG[100][100];
int timeG[100][100];

int main()
{
	int n, m, a, b, c, t;
	
	while (cin >> n >> m, n!=0 && m!=0) {
		rep(i, 100) {
			rep(j, 100) {
				costG[i][j]=INF;
				timeG[i][j]=INF;
			}
		}
		
		rep(k, n) {
			cin >> a >> b >> c >> t;
			a--; b--;
			costG[a][b] = c;
			costG[b][a] = c;
			timeG[a][b] = t;
			timeG[b][a] = t;
		}
		
		rep(k, m) {
			rep(i, m) {
				rep(j, m) {
					costG[i][j] = min(costG[i][j], costG[i][k]+costG[k][j]);
					timeG[i][j] = min(timeG[i][j], timeG[i][k]+timeG[k][j]);
				}
			}
		}
		
		int k, p, q, r;
		cin >> k;
		rep(i, k) {
			cin >> p >> q >> r;
			p--; q--;
			if (r==0) {
				cout << costG[p][q] << endl;
			} else {
				cout << timeG[p][q] << endl;
			}
		}
	}
	return 0;
}

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

int main()
{
	while(true){
		scanf("%d%d",&N,&M);
		if(N==0&&M==0)return 0;
		int cost[200][200];
		int time[200][200];
		int minc[200][200];
		int mint[200][200];
		for(int i=0;i<M;i++){
			for(int j=0;j<M;j++){
				cost[i][j]=1<<25;
				time[i][j]=1<<25;
				minc[i][j]=1<<25;
				mint[i][j]=1<<25;
				if(i==j){
					cost[i][j]=0;
					time[i][j]=0;
					minc[i][j]=0;
					mint[i][j]=0;
				}
			}
		}
		int A,B,co,ti;
		for(int i=0;i<N;i++){
			scanf("%d%d%d%d",&A,&B,&co,&ti);A--;B--;
			cost[A][B]=co;cost[B][A]=co;
			time[A][B]=ti;time[B][A]=ti;
		}
		for(int i=0;i<M;i++){
			for(int j=0;j<M;j++){
				for(int k=0;k<M;k++){
					cost[i][j]=min(cost[i][j],cost[i][k]+cost[k][j]);
					time[i][j]=min(time[i][j],time[i][k]+time[k][j]);
				}
			}
		}
		int K;
		scanf("%d",&K);
		for(int i=0;i<K;i++){
			int P,Q,R;
			scanf("%d%d%d",&P,&Q,&R);P--;Q--;
			if(R==0)printf("%d\n",cost[P][Q]);
			else printf("%d\n",time[P][Q]);
		}
	}
}