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 <stdio.h>
#include <vector>
#include <algorithm>
#include <math.h>
#include <queue>
 
using namespace std;
 
int main(){
 
    int n,m,min_time[101][101],min_cost[101][101],from,to,cost,time,num,r;
 
    while(true){
        scanf("%d %d",&n,&m);
        if(n == 0 && m == 0)break;
 
        for(int i = 1; i <= m; i++){
            for(int k = 1; k <= m; k++){
                if(i != k){
                    min_time[i][k] = 2000000000;
                    min_cost[i][k] = 2000000000;
                }else{
                    min_time[i][k] = 0;
                    min_cost[i][k] = 0;
                }
            }
        }
 
        for(int i = 0; i < n; i++){
            scanf("%d %d %d %d",&from,&to,&cost,&time);
            min_time[from][to] = time;
            min_cost[from][to] = cost;
            min_time[to][from] = time;
            min_cost[to][from] = cost;
        }
 
        for(int k = 1; k <= m; k++){
            for(int i = 1; i <= m; i++){
                if(min_time[i][k] == 2000000000)continue;
                for(int p = 1; p <= m; p++){
                    if(min_time[k][p] == 2000000000)continue;
                    min_time[i][p] = min(min_time[i][p],min_time[i][k] + min_time[k][p]);
                }
            }
 
            for(int i = 1; i <= m; i++){
                if(min_cost[i][k] == 2000000000)continue;
                for(int p = 1; p <= m; p++){
                    if(min_cost[k][p] == 2000000000)continue;
                    min_cost[i][p] = min(min_cost[i][p],min_cost[i][k] + min_cost[k][p]);
                }
            }
        }
 
        scanf("%d",&num);
 
        for(int i = 0; i < num; i++){
            scanf("%d %d %d",&from,&to,&r);
            if(r == 1){
                printf("%d\n",min_time[from][to]);
            }else{
                printf("%d\n",min_cost[from][to]);
            }
        }
    }
 
    return 0;
}

C++: #include <cstdio>
#include <vector>
#include <algorithm>
#include <queue>
using namespace std;

struct station
{
	station(int to, int cost, int time)
	{
		this->to = to;
		this->cost = cost;
		this->time = time;
	}

	int to;
	int cost;
	int time;
};

void dijkstra(int from, int mode);

vector<station> route[1000];
int mini[1000];
int n, m;

int main()
{
	while (scanf("%d %d", &n, &m) * n != 0){
		for (int i = 0; i < m; i++){
			route[i].clear();
		}
		for (int i = 0; i < n; i++){
			int a, b;
			int cost, time;
			
			scanf("%d %d %d %d", &a, &b, &cost, &time);
			a--, b--;
			route[a].push_back(station(b, cost, time));
			route[b].push_back(station(a, cost, time));
		}
		
		int k;
		scanf("%d", &k);
		while (k-- > 0){
			fill(mini, mini + m, 100000000);
			int p, q, r;
			scanf("%d %d %d", &p, &q, &r);
			p--, q--;
			mini[p] = 0;
			dijkstra(p, r);
			printf("%d\n", mini[q]);
		}
	}
	
	return 0;
}

void dijkstra(int from, int mode)
{
	queue<int> to;
	
	for (vector<station>::iterator i = route[from].begin(); i < route[from].end(); i++){
		if (mode == 0 && mini[i->to] > mini[from] + i->cost){
			mini[i->to] = mini[from] + i->cost;
			to.push(i->to);
		}
		else if (mode == 1 && mini[i->to] > mini[from] + i->time){
			mini[i->to] = mini[from] + i->time;
			to.push(i->to);
		}
	}
	while (!to.empty()){
		dijkstra(to.front(), mode);
		to.pop();
	}
}

C++: #include<stdio.h>
#define INF 10000000
int e1[100][100],e2[100][100];
int d[100];
bool used[100];
int m,n;
int p,q,r;
int k;
int i,j;
int a,b,t,c;
int v;
int mc,mt;

int min(int x,int y){
	if(x<=y)return x;
	else return y;
}

void solve(int s,int mo){
	for(j=0;j<m;j++){
		used[j]=false;
		d[j]=INF;
	}
	d[s]=0;
	while(true){
		v=-1;
		for(int u=0;u<m;u++)if(!used[u]&&(v==-1||d[u]<d[v]))v=u;
		if(v==-1)break;
		used[v]=true;
		for(int u=0;u<m;u++){
			if(mo==0)d[u]=min(d[u],d[v]+e1[v][u]);
			else d[u]=min(d[u],d[v]+e2[v][u]);
		}
	}
}


int main(){
	while(1){
		scanf("%d %d",&n,&m);
		if(n==0&&m==0)break;
		mt=INF;
		mc=INF;
		for(i=0;i<m;i++)for(j=0;j<m;j++){
			e1[i][j]=INF;
			e2[i][j]=INF;
		}
		for(i=0;i<n;i++){
			scanf("%d %d %d %d",&a,&b,&c,&t);
			e1[a-1][b-1]=c;
			e1[b-1][a-1]=c;
			e2[a-1][b-1]=t;
			e2[b-1][a-1]=t;
		}
		scanf("%d",&k);
		for(i=0;i<k;i++){
			scanf("%d %d %d",&p,&q,&r);
			solve(p-1,r);
			if(r==0)mc=min(mc,d[q-1]);
			else mt=min(mt,d[q-1]);
		}
		printf("%d\n%d\n",mc,mt);
	}
}

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

const int INF = 1000000000;

void WarshallFloyd(int d[100][100],int m){
	for(int k=0;k<m;k++){
		for(int i=0;i<m;i++){
			for(int j=0;j<m;j++){
				if(d[i][j]>d[i][k]+d[k][j]){
					d[i][j]=d[i][k]+d[k][j];
				}
			}
		}
	}
	return;
}

int main()
{
	while(true){
		int n, m;
		cin >> n >> m;

		if(n==0 && m==0)
			break;

		int C[100][100];
		int T[100][100];
		for(int i=0; i<m; i++){
			for(int j=0; j<m; j++){
				if(i==j){
					C[i][j] = T[i][j] = 0;
				}
				else{
					C[i][j] = T[i][j] = INF;
				}
			}
		}
		for(int i=0; i<n; i++){
			int a, b, c, t;
			cin >> a >> b >> c >> t;

			C[a-1][b-1] = C[b-1][a-1] = c;
			T[a-1][b-1] = T[b-1][a-1] = t;
		}

		WarshallFloyd(C,m);
		WarshallFloyd(T,m);

		int k,p,q,r;
		cin>>k;
		for(int i=0;i<k;i++){
			cin>>p>>q>>r;
			if(r==0) cout<<C[p-1][q-1]<<endl;
			if(r==1) cout<<T[p-1][q-1]<<endl;
		}


	}

	return 0;
}