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 <array>
#include <stack>

using namespace std;

int const Inf = 10000000;
int const N = 100;

typedef array<int, 2> line;

int main()
{
    int n, m;
    while( cin >> n >> m, n||m ) {
        line table[N][N] = {};

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

            int const from = a-1, to = b-1;
            line const in = {{cost, time}};
            table[from][to] = in;
            table[to][from] = in;
        }

        int k;
        cin >> k;
        for( int i=0; i<k; ++i ) {
            int p, q, r;
            cin >> p >> q >> r;
            int const from = p-1, to = q-1;
            int d[N];
            fill( d, d+N, Inf );

            stack<int> w;
            w.push( from );
            d[from] = 0;

            while( !w.empty() ) {
                int const cur = w.top();
                w.pop();

                for( int ii=0; ii<m; ++ii ) {
                    if ( table[cur][ii][0] == 0 )
                        continue;

                    if ( d[cur] + table[cur][ii][r] < d[ii] ) {
                        d[ii] = d[cur] + table[cur][ii][r];
                        w.push( ii );
                    }
                }
            }

            cout << d[to] << endl;
        }
    }
}

C++: #include <iostream>

using namespace std;

int main(void){
	int val;
	while(cin >> val)
		cerr << val << " ";

	return 0;
}

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

#define iota(i,n,b,s) for(int i=int(b);i!=int((b)+(s)*(n));i+=(s))
#define range(i,n,m) iota(i,(((n)>(m))?((n)-(m)+1):((m)-(n)+1)),(n),((n)>(m)?-1:1))
#define rep(i,n) iota(i,(n),0,1)

#define INF (1e9)
#define EPS (1e-9)
#define cons(a,b) (make_pair(a,b))
#define car(a) (a.first)
#define cdr(a) (a.second)
#define cadr(a) (car(cdr(a)))
#define cddr(a) (cdr(cdr(a)))
#define all(a) a.begin(), a.end()
#define trace(var) cerr<<">>> "<<#var<<" = "<<var<<endl;

typedef long long INTEGER;
typedef double FLOAT;

template<class S, class T>
ostream& operator<<(ostream& os, pair<S,T> p) {
  os << '(' << car(p) << ", " << cdr(p) << ')';
  return os;
}

template<class T>
ostream& operator<<(ostream& os, vector<T> v) {
  os << v[0];
  for (int i=1, len=v.size(); i<len; ++i) os << ' ' << v[i];
  return os;
}

const int MM = 3000;
int cost[MM][MM];
int toki[MM][MM];

int main() {

  int n, m; cin >> m >> n;

  rep (i, n) {
    rep (j, n) {
      cost[i][j] = INF;
      toki[i][j] = INF;
    }
    cost[i][i] = 0;
    toki[i][i] = 0;
  }

  rep (i, m) {
    int a, b, c, t;
    cin >> a >> b >> c >> t;
    --a; --b;
    cost[a][b] = cost[b][a] = c;
    toki[a][b] = toki[b][a] = t;
  }

  rep (k, n) {
    rep (i, n) {
      rep (j, n) {
        cost[i][j] = min(cost[i][j], cost[i][k] + cost[k][j]);
        toki[i][j] = min(toki[i][j], toki[i][k] + toki[k][j]);
      }
    }
  }

  //rep (i,n) { rep(j,n) { cout << cost[i][j] << ' '; } cout << endl; }

  int k; cin >> k;
  rep (i, k) {
    int a, b, t;
    cin >> a >> b >> t;
    --a; --b;
    if (t) {
      cout << toki[a][b] << endl;
    } else {
      cout << cost[a][b] << endl;
    }
  }

  return 0;
}

C++: #include <iostream>
#include <algorithm>
using namespace std;
const int INF = 1000000;
int cost[101][101],ttime[101][101];
int main(){
	int n,m;
	while(cin >> n >> m,n || m){
		int a,b,icost,itime,c,r;
		for(int i = 0;i <= m;++i){
			for(int j = 0;j <= m;++j){
				if(i == j) {
					cost[i][i] = 0;
					ttime[i][i] = 0;
				}
				else {
					cost[i][j] = INF;
					ttime[i][j] = INF;
				}
			}
		}
		for(int i = 0;i < n;++i){
			cin >> a >> b >> icost >> itime;
			cost[a][b] = cost[b][a] = icost;
			ttime[a][b] = ttime[b][a] = itime;
		}
		cin >> c;
		for(int d = 0;d < c;++d){
			cin >> a >> b >> r;
			for(int k = 0;k <= m;++k){
				for(int i = 0;i <= m;++i){
					for(int j = 0;j <= m;++j){
						if(r == 1) ttime[i][j] = min(ttime[i][j],ttime[i][k] + ttime[k][j]);
						else cost[i][j] = min(cost[i][j],cost[i][k] + cost[k][j]);
					}
				}
			}
			if(r == 1) cout << ttime[a][b] << endl;
			else cout << cost[a][b] << endl;
		}
	}
	return 0;
}

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

using namespace std;

#define INF 1000000

int s, e, r, n, m;

int dijk(int d[][101]) {
  int mi, i, j;
  int c[m + 1] = {};
    
  for(i = 0; i <= m; i++) {
    c[i] = INF;
  }
    
  int f[m + 1] = {};
  mi = s;
  c[s] = 0;

  for(i = 0; i < m; i++){
    f[mi] = 1;

    for(j = 0; j <= m; j++) {
      if(f[j] == 1) continue;
      if(c[j] > d[j][mi] + c[mi]) {
	c[j] = d[j][mi] + c[mi];
	//	cout << j << c[j] << endl;
      }
    }

    int MIN = INF * 2;

    for(j = 0; j <= m; j++) {
      if(f[j] == 1) continue;
      if(MIN > c[j]) {
	MIN = c[j];
	mi = j;
      }
    }
  }
  return c[e];
}

  
int main() {
  int i, j,k, a,b, cost, time;
  while(cin >> n >> m, n != 0 || m != 0) {
    int d[101][101] = {};
    int T[101][101] = {};

    
    for(i = 0; i <= m; i++) {
      for(j = 0;j <= m; j++) {
	d[i][j] = T[i][j] = INF;
      }
    }
    
    for(i = 0; i < n; i++) {
      cin >> a >> b >> cost >> time;
      d[a][b] = d[b][a] = cost;
      T[a][b] = T[b][a] = time;
    }
    
    cin >> k;
    for(i = 0; i < k; i++) {
      cin >> s >> e >> r;
      if(r == 0) cout << dijk(d) << endl;
      else cout << dijk(T) << endl;
    }
  }
  return 0;
}