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<algorithm>
#include<cstring>
#define INF 111111111
using namespace std;

int n,m;
int a,b,c,d,cost[1000][1000],tim[1000][1000];
int memo[1000];
int ans[1000],ans2[1000];
int p,q,r;
int k,x,y,z;

void cost_a(){
  ans[x] = 0;

  while(true){
    int s = -1;

    for(int i=1;i<=m;i++){
      if(!memo[i] && (s == -1 || ans[i] < ans[s])) s = i;
    }

    if(s == -1) break;
    memo[s] = 1;

    for(int i=1;i<=m;i++) ans[i] = min(ans[i],ans[s] + cost[i][s]);
  }
}

void time_a(){
  ans2[x] = 0;

  while(true){
    int s = -1;

    for(int i=1;i<=m;i++){
      if(!memo[i] && (s == -1 || ans[i] < ans2[s])) s = i;
    }

    if(s == -1) break;
    memo[s] = 1;

    for(int i=1;i<=m;i++) ans2[i] = min(ans2[i],ans2[s] + tim[i][s]);
  }
}

int main(){

  while(true){
    cin >> n >> m;
    if(!n && !m) break;

    for(int i=0;i<1000;i++){
      for(int j=0;j<1000;j++) cost[i][j] = tim[i][j] = INF;
    }

    for(int i=0;i<n;i++){
      cin >> a >> b >> c >> d;
     
      if(cost[a][b] > c) cost[a][b] = cost[b][a] = c;
      if(tim[a][b] > d) tim[a][b] = tim[b][a] = d;

    }

    cin >> k;

    for(int i=0;i<k;i++){
      cin >> x >> y >> z;

      memset(memo,0,sizeof(memo));
      for(int i=0;i<1000;i++) ans[i] = ans2[i] = INF;

      if(!z){
	cost_a();
	cout << ans[y] << endl;
      }

      else{
	time_a();
	cout << ans2[y] << endl;
      }
    }
  }
}

C++: #include<cstdio>
#include<algorithm>
#define MIN(x,y) ((x<y)? x:y)

using namespace std;




int main()
{
	while(true)
	{
int timedate[2][105][105]={0};
int n,m;
	scanf("%d%d",&n,&m);
	if(n==0&&m==0)break;
	int a, b, cost,time;
	for(int i=0;i<6;i++)
	{
		scanf("%d%d%d%d",&a,&b,&cost,&time);
		timedate[0][a][b]=cost;
		timedate[0][b][a]=cost;
		timedate[1][a][b]=time;
		timedate[1][b][a]=time;
	}
	int k;
	scanf("%d",&k);
	for(int i=0;i<k;i++)
	{
		int p,q,r;
		int date[105];
		int omin=1000000,jmin;
		fill(date,date+100,-1);
		scanf("%d%d%d",&p,&q,&r);
		date[p]=0;
		
			for(int u=1;u<100;u++)
			{
			omin=1000000;
			jmin=0;
		for(int j=1;j<100;j++)
		{
			if(date[j]!=-1)
			{
				for(int o=1;o<101;o++)
				{
					if(timedate[r][j][o]!=0&&o!=-1&&omin>date[j]+timedate[r][j][o]&&date[o]==-1)
					{
						omin=date[j]+timedate[r][j][o];
						jmin=o;
					}
				}
			}
		}
		date[jmin]=omin;
			}
		printf("%d\n",date[q]);
	}
	}
	return 0;
}

C++: #include<iostream>
#include<algorithm>
using namespace std;

struct edge {
	int money;
	int time;
};

int main(){
	int n, m;
	int count;
	edge G[100][100];

	while(cin >> n >> m, n || m){
		for(int i=0; i < 100; i++){
			for(int j=0; j < 100; j++){
				G[i][j].money = 1000000;
				G[i][j].time = 1000000;
			}
		}

		for(int i=0; i < n; i++){
			int a, b, mo, t;
			cin >> a >> b >> mo >> t;

			G[a][b].time=t;
			G[a][b].money=mo;
			G[b][a].time=t;
			G[b][a].money=mo;
		}

		for(int k=0; k < n; k++){
			for(int i=0; i < n; i++){
				for(int j=0; j < n; j++){
					G[i][j].time = min(G[i][j].time, G[i][k].time+G[k][j].time);
					G[i][j].money = min(G[i][j].money, G[i][k].money+G[k][j].money);
				}
			}
		}

		cin >> count;
		for(int i=0; i < count; i++){
			int p;
			cin >> n >> m >> p;

			if(p==1) cout << G[n][m].time << endl;
			else cout << G[n][m].money << endl;
		}
	}
	return 0;
}