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<iomanip>
#include<math.h>
#include<algorithm>
#include<string>
#include<vector>
#include<queue>
#include<stack>
#include<set>
#include<map>
#define REP(i, N) for(ll i = 0; i < N; ++i)
#define FOR(i, a, b) for(ll i = a; i < b; ++i)
#define ALL(a) (a).begin(),(a).end()
#define pb push_back
#define INF (long long)1000000000
#define MOD 1000000007
using namespace std;
typedef long long ll;
typedef pair<ll, ll> P;
int dx[4] = {1, 0, -1, 0};
int dy[4] = {0, 1, 0, -1};

int main(void) {
	while(true) {
		int n, m;
		cin>>n>>m;
		if(n == 0 && m == 0) break;
		vector<vector<pair<ll, P> > > l(m, vector<pair<ll, P> >(0));
		REP(i, n) {
			ll a, b, c, t;
			cin>>a>>b>>c>>t;
			--a;
			--b;
			l[a].pb(pair<ll, P>(b, P(c, t)));
			l[b].pb(pair<ll, P>(a, P(c, t)));
		}
		vector<vector<ll> > d0(m, vector<ll>(m, INF));
		vector<vector<ll> > d1(m, vector<ll>(m, INF));
		REP(i, m) {
			REP(j, l[i].size()) {
				d0[i][l[i][j].first] = l[i][j].second.first;
				d0[l[i][j].first][i] = l[i][j].second.first;
				d1[i][l[i][j].first] = l[i][j].second.second;
				d1[l[i][j].first][i] = l[i][j].second.second;
			}
		}
		REP(k, m) {
			REP(i, m) {
				REP(j, m) {
					d0[i][j] = min(d0[i][j], d0[i][k] + d0[k][j]);
					d1[i][j] = min(d1[i][j], d1[i][k] + d1[k][j]);
				}
			}
		}
		int k;
		cin>>k;
		REP(i, k) {
			int p, q, r;
			cin>>p>>q>>r;
			--p;
			--q;
			if(r == 0) {
				cout<<d0[p][q]<<endl;
			} else {
				cout<<d1[p][q]<<endl;
			}
		}
	}
}

C++: #include<iostream>
#include<queue>
#include<vector>
#include<map>
using namespace std;
typedef pair<int,int> P;
typedef struct{
	int next;
	int cost;
	int time;
}edge;

int n,m;
vector<edge> mapp[3001];
int bfs_c(int now,int goal);
int bfs_t(int now,int goal);

int main(){
	while(1){
		cin >> n >> m;
		if(n == 0 && m == 0) break;
		for(int i=0;i<n;i++){
			int a,b,cost,time;
			cin >> a >> b >> cost >> time;
			edge x;
			x.next = b; x.cost = cost; x.time = time;
			mapp[a].push_back(x);
		}
		int k;
		cin >> k;
		int ans;
		for(int i=0;i<k;i++){
			int p,q,r;
			cin >> p >> q >> r;
			if(r == 0) ans = bfs_c(p,q);
			else if(r == 1) ans = bfs_t(p,q);
			cout << ans << endl;
		}
	}
}

int bfs_c(int now,int goal){
	priority_queue<P, vector<P>,greater<P> > que;
	que.push(P(now,0));
	while(!que.empty()){
		P p = que.top(); que.pop();
		int no = p.first;
		int co = p.second;
		if(no == goal) return co;
		int len=mapp[no].size();
		for(int i=0;i<len;i++){
			edge x = mapp[no][i];
			que.push(P(x.next,co+x.cost));
		}
	}
	return 0;
}

int bfs_t(int now,int goal){
	priority_queue<P, vector<P>,greater<P> > que;
	que.push(P(now,0));
	while(!que.empty()){
		P p = que.top(); que.pop();
		int no = p.first;
		int co = p.second;
		if(no == goal) return co;
		int len=mapp[no].size();
		for(int i=0;i<len;i++){
			edge x = mapp[no][i];
			que.push(P(x.next,co+x.time));
		}
	}
	return 0;
}

C++: #include<iostream>
using namespace std;
#include<algorithm>
#define REP(i,a) for(int  i=0;i<a;i++)
int A[101][101];
int B[101][101];
int main(){
	int a,b=0,c=0,d,n,m;	
	cin>>n>>m;
	while(n!=0||m!=0){
	REP(i,m){
		REP(j,m){
			A[i][j]=1001;
			B[i][j]=1001;
		}
	}
	REP(i,n){
	cin>>a>>b>>c>>d;
	A[a-1][b-1]=c;
	B[a-1][b-1]=d;	
	A[b-1][a-1]=c;
	B[b-1][a-1]=d;
	}
	REP(k,m){
		REP(i,m){
	 		REP(j,m){
		A[i][j]=min(A[i][j],A[i][k]+A[k][j]);
		B[i][j]=min(B[i][j],B[i][k]+B[k][j]);

			}
		}	
	}
	cin>>n;
	REP(i,n){
	cin>>a>>b>>c;
	if(c==0) cout<<A[a-1][b-1]<<endl;
	else cout<<B[a-1][b-1]<<endl;
	}
	cin>>n>>m;
	}
	return 0;
}

C++: #include<stdio.h>
#include<algorithm>
#include <map>
#include <list>
#include <stack>
#include <queue>
#include <vector>
#include <iostream>
#include <functional>
#include <time.h>
using namespace std;
clock_t fi, endtime;

const int INF = 2147483647;
const int r_c = 0;
const int r_t = 1;
const int MAX_V = 100;
const int MAX_E = 6000;

int n, m, a, b, c, t;
int k, p, q, r;

int wft[MAX_V][MAX_V] = { 0 };
int wfc[MAX_V][MAX_V] = { 0 };

int main()
{
	scanf("%d %d", &n, &m);
	for (int i = 0; i < m; ++i) {
		for (int j = 0; j < m; ++j) {
			wfc[i][j] = INF; wft[i][j] = INF;
		}
	}

	for (int i = 0; i < n; ++i) {
		scanf("%d %d %d %d", &a, &b, &c, &t);
		wft[a - 1][b - 1] = t;  wft[b - 1][a - 1] = t;
		wfc[a - 1][b - 1] = c;  wfc[b - 1][a - 1] = c;
	}
	for (int k = 0; k < m; ++k) {
		for (int i = 0; i < m; ++i) {
			for (int j = 0; j < m; ++j) {
				if (wft[i][j] > wft[i][k] + wft[k][j]) { wft[i][j] = wft[i][k] + wft[k][j]; }
				if (wfc[i][j] > wfc[i][k] + wfc[k][j]) { wfc[i][j] = wfc[i][k] + wfc[k][j]; }
			}
		}
	}
	scanf("%d", &k);
	int ans = 0;
	for (int i = 0; i < k; ++i){
		scanf("%d %d %d", &p, &q, &r);
		if (p == 0 && q == 0) break;
		if (r == 0) { ans = wfc[p - 1][q - 1]; }
		else { ans = wft[p - 1][q - 1]; }
		printf("%d\n", ans);
	}

}