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
			c_matrix[b-1][a-1] = c
			t_matrix[a-1][b-1] = t
			t_matrix[b-1][a-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>
using namespace std;

#define rep(i, n) for(int i = 0;i < (int)n;i++)
#define rep2(i, n) for(int i = 1;i <= (int)n;i++)

int c[101][101];
int t[101][101];

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

        rep(i, 101) {
            rep(j, 101) {
                c[i][j] = t[i][j] = (i != j ? 1001 : 0);
            }
        }

        rep(i, n) {
            int a, b, cost, time;
            cin >> a >> b >> cost >> time;
            c[a][b] = c[b][a] = cost;
            t[a][b] = t[b][a] = time;
        }

        rep2(i, m) {
            rep2(j, m) {
                rep2(k, m) {
                    c[i][j] = min(c[i][j], c[i][k] + c[k][j]);
                    t[i][j] = min(t[i][j], t[i][k] + t[k][j]);
                }
            }
        }

        int k;
        cin >> k;
        rep(i, k) {
            int p, q, r;
            cin >> p >> q >> r;
            cout << (r == 0 ? c[p][q] : t[p][q]) << endl;
        }
    }

    return 0;
}

C++: #include<iostream>
#include<algorithm>
#define MAX 1000000
using namespace std;
int main(){
	int n, m, a, b, cost, ti, k, p, q, r, point = 0;
	int cost_[101][101], time_[101][101], k_[101];
	for (int i = 0; i < 101; i++){
		for (int l = 0; l < 101; l++){
			cost_[i][l] = MAX;
			time_[i][l] = MAX;
		}
	}
	cin >> n >> m;
	while (n != 0 && m != 0){
		for (int i = 0; i < n; i++){
			cin >> a >> b >> cost >> ti;
			cost_[a][b] = cost;
			time_[a][b] = ti;
		}
		cin >> k;
		for (int i = 0; i < k; i++){
			cin >> p >> q >> r;
			k_[point] = p;
			k_[point + 1] = q;
			k_[point + 2] = r;
			point += 3;
		}point = 0;
		for (int i = 1; i <= m; i++){
			for (int j = 1; j <= m; j++){
				for (int o = 1; o <= m; o++){
					if (cost_[j][i] != MAX && cost_[i][o] != MAX &&
						time_[j][i] != MAX && time_[i][o] != MAX){
						cost_[j][o] = min(cost_[j][o], cost_[j][i] + cost_[i][o]);
						time_[j][o] = min(time_[j][o], time_[j][i] + time_[i][o]);
					}
				}
			}
		}
		for (int i = 0; i < k; i++){
			if (k_[point + 2] == 0){
				cout << cost_[k_[point]][k_[point + 1]] << endl;
			}
			else cout << time_[k_[point]][k_[point + 1]] << endl;
			point += 3;
		}point = 0;
		cin >> n >> m;
	}
	return 0;
}

C++: #include <iostream>
#include <algorithm>
#include <climits>

#define INF INT_MAX / 2
#define REP(i, m, n) for(int i = m; i < static_cast<int>(n); ++i)
int main()
{
    int line_num, station_num;
    
    while (std::cin >> line_num >> station_num) {
        
        if (line_num == 0 && station_num == 0) break;

        int map[2][101][101];
        
        REP(i, 0, 2) REP(j, 0, 101) REP(k, 0, 101) map[i][j][k] = INF;
        
        REP(i, 0, line_num) {
            int a, b, cost, time;
            std::cin >> a >> b >> cost >> time;
            map[0][a][b] = map[0][b][a] = cost;
            map[1][a][b] = map[1][b][a] = time;
        }
        
        REP(l, 0, 2) {
            REP(i, 1, station_num + 1) {
                REP(j, 1, station_num + 1) {
                    REP(k, 1, station_num + 1) {
                        map[l][i][j] = std::min(map[l][i][j], map[l][i][k] +
                                                map[l][k][j]);
                    }
                }
            }
        }

        int input_num;

        std::cin >> input_num;

        REP(i, 0, input_num) {
            int p, q, r;

            std::cin >> p >> q >> r;
            std::cout << map[r][p][q] << std::endl;
        }
    
    }
    return 0;
}

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

const int INF = 1000000000;

int main()
{
  int count=0;
	while(count=50){
		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;
    }

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

	return 0;
}