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 <cstdio>
#include <cstdlib>
#include <cstring>
#include <cmath>
#include <iostream>
#include <vector>
#include <string>
#include <sstream>
#include <algorithm>
#include <utility>
#include <set>
#include <map>
#include <stack>
#include <queue>
#include <deque>
#include <functional>
 
using namespace std;
 
#define fst first
#define scd second
#define PB push_back
#define MP make_pair
#define chmin(a,b) a=min(a,b)
#define chmax(a,b) a=max(a,b)
#define rep(i,x) for(int i=0;i<(x);++i)
#define rep1(i,x) for(int i=1;i<=(x);++i)
#define rrep(i,x) for(int i=(x)-1;i>=0;--i)
#define rrep1(i,x) for(int i=(x);i>=1;--i)
#define FOR(i,a,x) for(int i=(a);i<(x);++i)
#define all(a) a.begin(),a.end()
#define rall(a) a.rbegin(),a.rend()
 
template<typename T>T&get(){T a;cin >> a;return a;}
template<typename T>T&rev(T&a){reverse(all(a));return a;}
template<typename T>istream&operator>>(istream&is,vector<T>&vec){rep(i,vec.size())is>>vec[i];return is;}
template<typename T>vector<T>&sort(vector<T>a){sort(all(a));return a;}
 
typedef long long ll;
typedef vector<int> vi;
typedef pair<int, int> pii;
 
const int inf = 1e9;
const ll linf = 3e18;
 
struct edge {
    int to, cost, time;
    edge(int to0,int cost0,int time0) {
        to = to0; cost = cost0; time = time0;
    };
};
 
int N, M;
 
vector<edge> G[100];
int d[100];
 
void dijkstra(int s, int mode)
{
    priority_queue<pii, vector<pii>, greater<pii> > q;
 
    fill(d, d + M, inf);
    d[s] = 0;
 
    q.push(MP(0, s));
 
    while (q.size()) {
        pii p = q.top(); q.pop();
        int v = p.scd;
        if (p.fst > d[v]) continue;
        rep(u, G[v].size()) {
            edge e = G[v][u];
            int a = mode == 0 ? e.cost : e.time;
            if (d[e.to] > d[v] + a) {
                d[e.to] = d[v] + a;
                q.push(MP(d[e.to], e.to));
            }
        }
    }
}
 
signed main()
{
    ios::sync_with_stdio(false);
    cin.tie(0);
 
    while (cin >> N >> M, N || M) {
        rep(i, M) G[i].clear();
 
        rep(i, N) {
            int a, b, cost, time; cin >> a >> b >> cost >> time; a--; b--;
            G[a].PB(edge(b, cost, time));
            G[b].PB(edge(a, cost, time));
        }
 
        int K; cin >> K;
 
        rep(i, K) {
            int p, q, r; cin >> p >> q >> r; p--; q--;
            dijkstra(p, r);
            cout << d[q] << endl;
        }
    }
}

C++: #include<iostream>
#include<cstring>
#include<algorithm>
using namespace std;
int x[1000][1000][2], n, m, a, b, c, d, q;

int path(int n, int s, int g) {
	int p[1000];
	memset(p, 127, sizeof(p));
	p[s] - 0;
	for (int i = 0; i < n; i++){
		for (int j = 1; j <= n; j++) {
			for (int k = 1; k <= n; k++) {
				if (x[j][k][1] < 10000000) {
					p[k] = min(p[k], p[j] + x[j][k][1]);
				}
			}
		}
	}
	return p[g];
}

int score(int n, int s, int g) {
	int p[1000];
	memset(p, 127, sizeof(p));
	p[s] - 0;
	for (int i = 0; i < n; i++) {
		for (int j = 1; j <= n; j++) {
			for (int k = 1; k <= n; k++) {
				if (x[j][k][0] < 10000000) {
					p[k] = min(p[k], p[j] + x[j][k][0]);
				}
			}
		}
	}
	return p[g];
}

int main() {
	while (true) {
		memset(x, 0, sizeof(x));
		cin >> m >> n;
		if (m == 0 && n == 0) { break; }
		for (int i = 0; i < m; i++) {
			cin >> a >> b >> c >> d;
			x[a][b][0] = c;
			x[b][a][0] = c;
			x[a][b][1] = d;
			x[b][a][1] = d;
		}
		cin >> q;
		for (int i = 0; i < q; i++) {
			cin >> a >> b >> c;
			if (c == 0) { cout << score(n, a, b); }
			else { cout << path(n, a, b); }
		}
	}
}

C++: #include<iostream>
#include<algorithm>
const int INF = 1<<20;
const int N = 101;
int cost[N][N];
int tim[N][N];
using namespace std;
int main()
{
	int n, m, a, b, co, ti,r;
	while (1){
		cin >> n >> m;
		if (n == 0 && m == 0)return 0;
		for (int i = 0; i < N; i++){
			for (int i2 = 0; i2 < N; i2++){
				cost[i][i2] = INF;
				tim[i][i2] = INF;
			}
		}
		for (int i = 0; i < n; i++){
			cin >> a >> b >> co >> ti;
			cost[a][b] = co;
			cost[b][a] = co;
			tim[a][b] = ti;
			tim[b][a] = ti;
		}
		for (int k = 0; k < m+1; ++k)
			for (int i = 0; i < m+1; ++i)
				for (int j = 0; j < m+1; ++j)
				{
					cost[i][j] = min(cost[i][j], cost[i][k] + cost[k][j]);
					tim[i][j] = min(tim[i][j], tim[i][k] + tim[k][j]);
				}
		cin >> m;
		for (int i = 0; i < m; i++){
			cin >> a >> b >> r;
			if (r == 0){
				cout << cost[a][b] << endl;
			}
			else
				cout << tim[a][b] << endl;
		}
	}
}

C++: /* Warshall-Floyd Algorithm */

#include<iostream>
#include<algorithm>

using namespace std;

int main()
{
	int cost[101][101],time[101][101];

	for(int n,m;cin>>n>>m,n;){
		for(int i=1;i<=m;i++)
			for(int j=1;j<=m;j++)
				cost[i][j]=time[i][j]=1<<29;

		for(int i=0;i<n;i++){
			int a,b,c,t;	cin>>a>>b>>c>>t;
			cost[a][b]=cost[b][a]=c;
			time[a][b]=time[b][a]=t;
		}

		for(int l=1;l<=m;l++){
			for(int i=1;i<=m;i++){
				for(int j=1;j<=m;j++){
					cost[i][j]=min(cost[i][j],cost[i][l]+cost[l][j]);
					time[i][j]=min(time[i][j],time[i][l]+time[l][j]);
				}
			}
		}

		int k;	cin>>k;
		while(k--){
			int p,q,r;	cin>>p>>q>>r;
			cout<<(r?time[p][q]:cost[p][q])<<endl;
		}
	}

	return 0;
}