Go: // Warshall–Floyd Algorithm

package main

import (
	"bufio"
	"fmt"
	"os"
	"strconv"
	"strings"
)

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
					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>
using namespace std;
struct Line{
        int a;
        int b;
        int cost;
        int time;
};
int Min(int x,int y){
        return x<y?x:y;
}
#define Max 2000000000
int main(){
        int N,M;
        while(true){
                Line lines[3000];
                cin >> N >>M;
                if(N+M==0)      break;
                for(int i=0 ; i<N ; i++ ){
                        cin >> lines[i].a >> lines[i].b ;
                        cin >> lines[i].cost >> lines[i].time;
                }
                int K;
                cin >> K;
                for(int i=0 ; i<K ; i++ ){
                        int to,from,r;
                        cin >> from >> to>>r;
                        queue <int> circle;
                        circle.push(from);
                        int dp[3000];
                        for(int i=0 ; i<=M ; i++ )
                                dp[i]=Max;
                        dp[from]=0;
                        while(circle.size()!=0){
                                int now=circle.front();
                                for(int i=0 ; i<N ; i++ ){
                                        if(now==lines[i].a){
                                                int next=lines[i].b;
                                                if(!r)
                                                        dp[next]=Min(dp[next],dp[now]+lines[i].cost);
                                                else
                                                        dp[next]=Min(dp[next],dp[now]+lines[i].time);
                                                circle.push(lines[i].b);
                                        }
                                }
                                circle.pop();
                        }
                        cout << dp[to] << endl;
                }
        }
        return 0;
}

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

#define REP(i,p,n) for(int i=p;i<n;++i)
#define rep(i,n) REP(i,0,n)

typedef pair<int,int> pii;
const int INF=1e8, MAXM=128;
int C[2][MAXM][MAXM], dist[MAXM], visited[MAXM], N, M;

int main()
{
        int a,b,c,d;
        cin>>N>>M;
        rep(i,M) rep(j,N) C[0][i][j]=C[1][i][j]=(i==j?0:INF);
        rep(i,N){ cin>>a>>b>>c>>d; --a; --b; C[0][a][b]=C[0][b][a]=c; C[1][a][b]=C[1][b][a]=d; }

        cin>>d;
        rep(i,d)
        {
                fill(dist,dist+MAXM,INF);
                fill(visited,visited+MAXM,false);

                cin>>a>>b>>c; --a; --b;
                dist[a]=0;

                while(true)
                {
                        int from=-1;
                        rep(i,M) if(!visited[i]&&(from==-1||dist[i]<dist[from])){ from=i; }
                        if(from==b){ cout<<dist[from]<<endl; break; } else { visited[from]=true; }

                        rep(to,M) if(dist[from]+C[c][from][to]<dist[to]){ dist[to]=dist[from]+C[c][from][to]; }
                }
        }

        return 0;
}

C++: #include<cstdio>
#include<algorithm>
#include<cstring>

int main(){
	using namespace std;
	int table[300][300][2],n,m,a,b,INF=10000000;
	while(true){
		scanf("%d%d",&n,&m);
		if(n==0&&m==0) break;
		for(int i=0;i<300;i++)
			for(int j=0;j<300;j++)
				for(int k=0;k<2;k++)
					table[i][j][k]=INF;
		for(int i=0;i<300;i++){
			table[i][i][0]=0;
			table[i][i][1]=0;
		}
		while(n--){
			scanf("%d%d",&a,&b);
			scanf("%d",&table[a-1][b-1][0]);
			table[b-1][a-1][0]=table[a-1][b-1][0];
			scanf("%d",&table[a-1][b-1][1]);
			table[b-1][a-1][1]=table[a-1][b-1][1];
		}

		for(int i=0;i<m;i++){
			for(int j=0;j<m;j++){
				for(int k=0;k<m;k++){
					table[j][k][0]=min(table[j][k][0],table[j][i][0]+table[i][k][0]);
					table[j][k][1]=min(table[j][k][1],table[j][i][1]+table[i][k][1]);
				}
			}
		}
		scanf("%d",&m);
		while(m--){
			scanf("%d%d%d",&a,&b,&n);
			printf("%d\n",table[a-1][b-1][n]);
		}
	}	
	return 0;

}

C++: #include<iostream>

#define INF 1001;
using namespace std;


int main(){
  int n,m;
  while(1){
    cin>>n>>m;
    if(n==0&&m==0)break;
    int s_tim[m][m];
    int c_money[m][m];
    int a,b,cost,tim;

    for(int i=0;i<m;i++){
      for(int j=0;j<n;j++){
        s_tim[i][j]=INF;
        c_money[i][j]=INF;
      }
    }
    for(int i=0;i<m;i++){
      s_tim[i][i]=0;
      c_money[i][i]=0;
    }
    for(int i=0;i<n;i++){
      cin>>a>>b>>cost>>tim;
      s_tim[a-1][b-1]=tim;s_tim[b-1][a-1]=tim;
      c_money[a-1][b-1]=cost;c_money[b-1][a-1]=cost;
    }

    for(int k=0;k<m;k++){
      for(int i=0;i<m;i++){
        for(int j=0;j<m;j++){
          if(s_tim[i][j]>s_tim[i][k]+s_tim[k][j]){
            s_tim[i][j]=s_tim[i][k]+s_tim[k][j];
          }
          if(c_money[i][j]>c_money[i][k]+c_money[k][j]){
            c_money[i][j]=c_money[i][k]+c_money[k][j];
          }
        }
      }
    }

    int contacts,p,q,r;
    cin>>contacts;

    for(int i=0;i<contacts;i++){
      cin>>p>>q>>r;
      if(r){cout<<s_tim[p-1][q-1];}
      else{ cout<<c_money[p-1][q-1];}
      cout<<endl;
    }
  }
}