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++: #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_ = 20000; // 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 = 1; i < 110; i++) {
			for (short j = 1; j < 110; j++) {
				if (i == j) {
					cost[i][j] = 0;
					time_data[i][j] = 0;
				} else {
					cost[i][j] = 20000;
					time_data[i][j] = 20000;
				}
			}
		}
		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<cstdio>
#include<algorithm>
#include<cstring>

using namespace std;




int main()
{
	while(true)
	{
int timedate[2][105][105];
int n,m;
    memset(timedate,0,sizeof(timedate));
	scanf("%d%d",&n,&m);
	if(n==0&&m==0)break;
	int a, b, cost,time;
	for(int i=0;i<n;i++)
	{
		scanf("%d%d%d%d",&a,&b,&cost,&time);
		timedate[0][a][b]=cost;
		timedate[0][b][a]=cost;
		timedate[1][a][b]=time;
		timedate[1][b][a]=time;
	}
	int k;
	scanf("%d",&k);
	for(int i=0;i<k;i++)
	{
		int p,q,r;
		int date[105];
		int omin=1000000,jmin;
		fill(date,date+100,-1);
		scanf("%d%d%d",&p,&q,&r);
		date[p]=0;
		
			for(int u=1;u<100;u++)
			{
			omin=1000000;
			jmin=0;
		for(int j=1;j<100;j++)
		{
			if(date[j]!=-1)
			{
				for(int o=1;o<101;o++)
				{
					if(timedate[r][j][o]!=0&&o!=-1&&omin>date[j]+timedate[r][j][o]&&date[o]==-1)
					{
						omin=date[j]+timedate[r][j][o];
						jmin=o;
					}
				}
			}
		}
		date[jmin]=omin;
		if(jmin==0)break;
			}
		printf("%d\n",date[q]);
	}
	}
	return 0;
}

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

using namespace std;
int clock[3001][3001];
int cost[3001][3001];


int main(){
	
	int i,j,k,a,b,t,c;
	int rail, station;
	int q,start,goal,dotti;
	int temp;
	
	


	while (1){
		
		cin >> rail >> station;
		
		if (rail == 0 && station == 0){
			break;
		}


		for (i = 0; i < station+1; i++){
			for (j = 0; j < station+1; j++){
				clock[i][j] = 1000000;
				cost[i][j] = 1000000;
			}
		}

		for (i = 0; i < rail; i++){
			cin >> a >> b >> c >> t;
			clock[a][b] = t;
			clock[b][a] = t;
			cost[a][b] = c;
			cost[b][a] = c;
		}


		cin >> q;

		for (;q>0;q--){
			cin >> start >> goal >> dotti;

			for (k = 1; k <= station; k++){
				for (i = 1; i <= station; i++){
					for (j = 1; j <= station; j++){
						cost[i][j] = min(cost[i][j], cost[i][k] + cost[k][j]);
					}
				}
			}

			for (k = 1; k <= station; k++){
				for (i = 1; i <= station; i++){
					for (j = 1; j <= station; j++){
						clock[i][j] = min(clock[i][j], clock[i][k] + clock[k][j]);
					}
				}
			}


			if (dotti == 0){
				cout << cost[start][goal] << endl;
			}

			if (dotti == 1){
				cout << clock[start][goal] << endl;
			}


		}
	


	}



}

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

using namespace std;

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

typedef array<int, 2> line;

struct tg { int c, v; };
bool operator>( tg const& lhs, tg const& rhs )
{
    return lhs.c > rhs.c;
}

int main()
{
    int n, m;
    priority_queue<tg, vector<tg>, greater<tg>> w;

    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] = ( 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;

            bool v[N] = {};
            int d[N];
            fill( d, d+N, Inf );

            tg const val = { 0, from };
            w.push( val );
            d[from] = 0;

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

                if ( v[cur] )
                    continue;
                v[cur] = true;

                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];
                        tg const val = { table[cur][ii][r], ii };
                        w.push( val );
                    }

                    //cout << cur+1 << " -> " << ii+1 << " c " << d[ii] << endl;
                }
                

            }

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