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);
		REP(i, n) {
			int 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)));
		}
		int k;
		cin>>k;
		REP(i, k) {
			int p, q, r;
			cin>>p>>q>>r;
			--p;
			--q;
			if(r == 0) {
				vector<ll> d(m, INF);
				priority_queue<P> que;
				que.push(P(0, p));
				d[p] = 0;
				while(!que.empty()) {
					P np = que.top();
					que.pop();
					if(d[np.second] != np.first) continue;
					REP(i, l[np.second].size()) {
						if(d[l[np.second][i].first] > d[np.second] + l[np.second][i].second.first) {
							d[l[np.second][i].first] = d[np.second] + l[np.second][i].second.first;
							que.push(P(d[l[np.second][i].first], l[np.second][i].first));
						}
					}
				}
				cout<<d[q]<<endl;
			} else {
				vector<ll> d(m, INF);
				priority_queue<P> que;
				que.push(P(0, p));
				d[p] = 0;
				while(!que.empty()) {
					P np = que.top();
					que.pop();
					if(d[np.second] != np.first) continue;
					REP(i, l[np.second].size()) {
						if(d[l[np.second][i].first] > d[np.second] + l[np.second][i].second.second) {
							d[l[np.second][i].first] = d[np.second] + l[np.second][i].second.second;
							que.push(P(d[l[np.second][i].first], l[np.second][i].first));
						}
					}
				}
				cout<<d[q]<<endl;
			}
		}
	}
}

C++: #define _CRT_SECURE_NO_WARNINGS

#include<fstream>
#include<iostream>
#include<string>
#include<iomanip>
#include<list>
#include<math.h>
#include<stack>
#include<queue>
#include<vector>
#include<algorithm>
#include<utility>

using namespace std;

short cost[110][110];
short time_data[110][110];


int main(){
	short n, m;


	while (cin >> n >> m && (n != 0 && m != 0)) {
		short min_ = 2000; // 答えの最小値
		short min_num = 1; // 答えの町

		short from, to, time_, cost_;
		short k;
		short k_from, k_to, info;

		for (short i = 0; i < 110; i++) {
			for (short j = 0; j < 110; j++) {
				cost[i][j] = 2000;
				time_data[i][j] = 2000;
			}
		}
		for (short i = 0; i < 110; i++) {
			cost[i][i] = 0;
		}
		for (short i = 0; i < n; i++) {
			cin >> from >> to >> cost_ >> time_;
			cost[from][to] = cost_;
			cost[to][from] = cost_;
			time_data[from][to] = time_;
			time_data[to][from] = time_;
		}
		for (short k = 1; k <= m; k++) {
			for (short i = 1; i <= m; i++) {
				for (short j = 1; j <= m; j++) {
					cost[i][j] = min((int)cost[i][j], cost[i][k] + cost[k][j]);

					time_data[i][j] = min((int)time_data[i][j], time_data[i][k] + time_data[k][j]);
				}
			}
		}
		// 答えを求める
		cin >> k;
		for (short i = 0; i < k; i++) {
			cin >> k_from >> k_to >> info;
			if (info == 0) {
				cout << cost[k_from][k_to] << endl;
			} else {
				cout << time_data[k_from][k_to] << endl;
			}
		}
		
  }
	return 0;
}

C++: #include <iostream>
#include <limits.h>

using namespace std;

int m;

int dijkstra( const int data[101][101], int start, int end )
{
	int i,j,next,min;
	bool visited[101];
	int distance[101];

	for( i = 1;i <= 100;i++ ){
		visited[i] = false;
		distance[i] = INT_MAX;
	}

	distance[start] = 0; next = start;

	do{
		i = next; visited[i] = true; min = INT_MAX;
		for(j = i;j <= m;j++){
			if(visited[j]) continue;
			if(data[i][j] < INT_MAX && distance[i] + data[i][j] < distance[j]) {
				distance[j] = distance[i] + data[i][j];
			}
			if( distance[j] < min ){
				min = distance[j]; next = j;
			}
		}
	} while( min < INT_MAX );

	return distance[end];
}


int main(int argc, char const* argv[])
{
	int n,weight[101][101][2];

	while( cin >> n >> m && n != 0 && m != 0 ){
		int a,b,c,d;
		for( int i = 0;i < 101;i++ ){
			for( int j = 0;j < 101;j++ ){
				weight[i][j][0] = INT_MAX;
				weight[i][j][1] = INT_MAX;
			}
		}

		for( int i = 0;i < n;i++ ){
			cin >> a >> b >> c >> d;
			weight[a][b][0] = c;
			weight[b][a][0] = c;
			weight[a][b][1] = d;
			weight[a][b][1] = d;
		}

		cin >> n;

		for( int i = 0;i < n;i++ ){
			int data[101][101];
			int p,q,r;
			cin >> p >> q >> r;
			for( int j = 1;j < 101;j++ ){
				for( int k = 1;k <101;k++ ) data[j][k] = weight[j][k][r];
			}
			cout << dijkstra( data, p, q ) << endl;
		}
	}


	return 0;

		
}

C++: #include<iostream>
using namespace std;
int c[110][110];
int t[110][110];
int main(){
	int n,m;
	cin>>n>>m;
	for(int i=1;i<=m;i++){
		for(int j=1;j<=m;j++){
			c[i][j]=t[i][j]=10000000;
		}
	}
	for(int i=0;i<n;i++){
		int a,b,cost,time;
		cin>>a>>b>>cost>>time;
		c[a][b]=c[b][a]=cost;
		t[a][b]=t[b][a]=time;
	}
	for(int x=1;x<=m;x++){
	for(int y=1;y<=m;y++){
		for(int i=1;i<=m;i++){
			for(int j=1;j<=m;j++){
				c[i][j]=min(c[i][j],c[i][y]+c[y][j]);
				t[i][j]=min(t[i][j],t[i][y]+t[y][j]);
			}
		}
	}
	}
	int k;
	cin>>k;
	for(int i=0;i<k;i++){
		int p,q,r;
		cin>>p>>q>>r;
		cout<<(r?t[p][q]:c[p][q])<<endl;
	}
	cin>>n>>m;
	return 0;
}