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>
#include <algorithm>
using namespace std;

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

const int INF = 10000000;
const int MAX_V = 100;
int d[2][MAX_V][MAX_V];

void solve() {
    while (true) {
        int E, V;
        cin >> E >> V;

        if (E == 0 && V == 0) break;

        //initialize
        REP(h, 2) {
            REP(i, V) {
                REP(j, V) {
                    if (i == j) d[h][i][j] = 0;
                    else        d[h][i][j] = INF;
                }
            }
        }

        //make graph
        REP(i, E) {
            int u, v, c1, c2;
            cin >> u >> v >> c1 >> c2;
            u--; v--;
            d[0][u][v] = c1; d[0][v][u] = c1;
            d[1][u][v] = c2; d[1][v][u] = c2;
        }

        //Warshall-Floyd
        REP(h, 2) {
            REP(k, V) {
                REP(i, V) {
                    REP(j, V) {
                        d[h][i][j] = min(d[h][i][j], d[h][i][k] + d[h][k][j]);
                    }
                }
            }
        }

        int K;
        cin >> K;

        REP(i, K) {
            int p, q, r;
            cin >> p >> q >> r;
            p--; q--;
            cout << d[r][p][q] << endl;
        }
    }
}


int main() {
    solve();
    return 0;
}

C++: #include <bits/stdc++.h>
#define r(i,n) for(int i=0;i<n;i++)
#define INF 1<<21
using namespace std;
main(){
  int m,n;
  while(cin>>m>>n,n){
    int a1[n][n],a2[n][n],q,w,e,r;
    r(i,n)r(j,n){
      if(i==j)a2[i][j]=a1[i][j]=0;
      else a2[n][n]=a1[i][j]=INF;
    }
    while(m--){
      cin>>q>>w>>e>>r;q--;w--;
      a1[q][w]=a1[w][q]=e;
      a2[q][w]=a2[w][q]=r;
    }
    r(k,n)r(i,n)r(j,n){
      a1[i][j]=min(a1[i][j],a1[i][k]+a1[k][j]);
      a2[i][j]=min(a2[i][j],a2[i][k]+a2[k][j]);
    }
    cin>>e;
    while(e--){
      cin>>q>>w>>r;q--;w--;
      if(r)cout<<a2[q][w]<<endl;
      else cout<<a1[q][w]<<endl;
    }
  }
}

C++: #include<cstdio>
#include<cstring>
#include<algorithm>
#include<functional>
#include<iostream>
#include<queue>
#define rep(i,a,b) for(i=a;i<b;i++)
#define F1 first.first
#define F2 first.second
#define F3 second
#define INF 2100000000
#define long long int int
using namespace std;
typedef pair<pair<int,int>,int> P1;
typedef pair<int,int> P2;
int main(void)
{
	int i,j,k,n,m,x,s,e;
	int a,b,cos,tim,st,en,way;
	int leng[1001],kami[1002];
	P1 glid1[6000],glid2[6000];
	P2 tori;
	while(1) {
		cin>>n>>m;
		if(n==0&&m==0) break;
		rep(i,0,n) {
			cin>>a>>b>>cos>>tim;
			glid1[i*2].F1=a,glid1[i*2].F2=b,glid1[i*2].F3=cos;
			glid2[i*2].F1=a,glid2[i*2].F2=b,glid2[i*2].F3=tim;
			glid1[i*2+1].F1=b,glid1[i*2+1].F2=a,glid1[i*2+1].F3=cos;
			glid2[i*2+1].F1=b,glid2[i*2+1].F2=a,glid2[i*2+1].F3=tim;
		}
		sort(glid1,glid1+m*2);sort(glid2,glid2+m*2);
		kami[1]=0;
		rep(i,1,m*2) {
			if(glid1[i].F1!=glid1[i-1].F1) {
				x=glid1[i].F1;
				kami[x]=i;
			}
		}
		kami[n+1]=m*2;
		priority_queue<P2,vector<P2>,greater<P2> > que;
		cin>>k;
		rep(i,0,k) {
			cin>>st>>en>>way;
			for(j=1;j<=n;j++) leng[j]=INF;
			//while(!que.empty()) que.pop();
			que.push(P2(0,st));
			while(!que.empty()) {
				tori=que.top(),que.pop();
				a=tori.first,b=tori.second;
				if(a<leng[b]) {
					leng[b]=a;
					if(b==en) break;
					s=kami[b],e=kami[b+1];
					if(way==0)rep(j,s,e) que.push(P2(a+glid1[j].F3,glid1[j].F2));
					else rep(j,s,e) que.push(P2(a+glid2[j].F3,glid2[j].F2));
				}
			}
			cout<<leng[en]<<endl;
		}
	}
	return 0;
}

C++: #include<cstdio>
#include<cstring>
#include<cstdlib>
#include<algorithm>
#include<functional>
#include<iostream>
#define INF 1000000
void cWarshall_Floyd();
void tWarshall_Floyd();
int glid_cost[100][100];
int glid_tim[100][100];
int n,m,a,b,tim,cost,qs,p,q,r;
using namespace std;
void cWarshall_Floyd()
{
	int i,j,k;
	for(k=0;k<m;k++) {
		for(i=0;i<m;i++) {
			for(j=0;j<m;j++) {
				glid_cost[i][j]=min(glid_cost[i][j],glid_cost[i][k]+glid_cost[k][j]);
			}
		}
	}
}
void tWarshall_Floyd()
{
	int i,j,k;
	for(k=0;k<m;k++) {
		for(i=0;i<m;i++) {
			for(j=0;j<m;j++) {
				glid_tim[i][j]=min(glid_tim[i][j],glid_tim[i][k]+glid_tim[k][j]);
			}
		}
	}
}
int main(void)
{
	ios::sync_with_stdio(false);
	int i,j,k;
	while(1) {
		cin>>n>>m;
		if(n==0&&m==0) break;
		for(i=0;i<m;i++) {
			for(j=0;j<m;j++) {
				glid_cost[i][j]=INF;
				glid_tim[i][j]=INF;
			}
		}
		for(i=0;i<m;i++) {
			glid_cost[i][i]=0;
			glid_tim[i][j]=0;
		}
		for(i=0;i<n;i++) {
			cin>>a>>b>>cost>>tim;
			a--;b--;
			glid_cost[a][b]=cost;
			glid_cost[b][a]=cost;
			glid_tim[a][b]=tim;
			glid_tim[b][a]=tim;
		}
		cin>>qs;
		for(i=0;i<qs;i++) {
			cin>>p>>q>>r;
			if(r==0) {
				cWarshall_Floyd();
				cout<<glid_cost[p-1][q-1]<<endl;
			}
			else {
				tWarshall_Floyd();
				cout<<glid_tim[p-1][q-1]<<endl;
			}
		}
	}
	return 0;
}