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>
using namespace std;

inline int max(int a, int b) { if (a>b) return a; else return b; }
inline int min(int a, int b) { if (a<b) return a; else return b; }

int min_route(int matrix[101][101], int n, int a, int b)
{
  int cost[101];
  bool done[101];
  int min_s = a;
  const int MAX = 999999999;

  for (int i=1; i<=n; i++)
  {
    cost[i] = MAX;
  }
  cost[a] = 0;
  while (!done[b])
  {
    done[min_s] = true;
    for (int i=1; i<=n; i++)
    {
      if ((matrix[min_s][i] > 0) && (cost[i] > cost[min_s]+matrix[min_s][i]))
      {
        cost[i] = cost[min_s]+matrix[min_s][i];
      }
    }
    int minin = MAX;
    for (int i=1; i<=n; i++)
    {
      if ((!done[i]) && (minin > cost[i]))
      {
        min_s = i;
        minin = cost[i];
      }
    }
  }
  return cost[b];
}


int main()
{
  int time[101][101];
  int cost[101][101];
  int n, m;
  int a, b, c, t;

  cin >> n >> m;

  for (int i=1; i<=m; i++)
    for (int j=1; j<=m; j++) { time[i][j] = 0; cost[i][j] = 0; }

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

  int k;
  int p, q, r;
  cin >> k;
  for (int i=1; i<=k; i++)
  {
    cin >> p >> q >> r;
    if (r==0)
    {
      cout << min_route(cost, m, p, q) << endl;
    }
    else
    {
      cout << min_route(time, m, p, q) << endl;
    }
  }
  return 0;
}

C++: #include <iostream>
using namespace std;

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

typedef pair<int,int> pii;
const int INF=1e6, MAXM=128;
int C[2][MAXM][MAXM], dist[MAXM], visited[MAXM], N, M;

int main()
{
        int a,b,c,d;
        cin>>N>>M;
        rep(i,M) rep(j,N) C[0][i][j]=C[1][i][j]=INF;
        rep(i,N){ cin>>a>>b>>c>>d; --a; --b; C[0][a][b]=C[0][b][a]=c; C[1][a][b]=C[1][b][a]=d; }

        cin>>d;
        rep(i,d)
        {
                fill(dist,dist+MAXM,INF);
                fill(visited,visited+MAXM,false);

                cin>>a>>b>>c; --a; --b;
                dist[a]=0;

                while(true)
                {
                        int from=-1;
                        rep(i,M) if(!visited[i]&&(from==-1||dist[i]<dist[from])){ from=i; }
                        if(from==b){ cout<<dist[from]<<endl; break; } else { visited[from]=true; }

                        rep(to,M) dist[to]=min(dist[to],dist[from]+C[c][from][to]);
                }
        }

        return 0;
}

C++: #include <iostream>
using namespace std;
#define INF 1000000
int time[110][110];
int cost[110][110];
int main()
{
    int n,m;
    while(cin>>n>>m,n){
        for(int i=0;i<m;++i){
            for(int j=0;j<m;++j){
                int a;
                i==j?a=0:a=INF;
                time[i][j]=a;
                cost[i][j]=a;
            }
        }
        for(int i=0;i<n;++i){
            int a,b,c,t;
            cin>>a>>b>>c>>t;
            a--;b--;
            cost[a][b]=c;
            cost[b][a]=c;
            time[a][b]=t;
            time[b][a]=t;
        }
        for(int k=0;k<m;++k){
            for(int i=0;i<m;++i){
                for(int j=0;j<m;++j){
                    cost[i][j]=min(cost[i][j],cost[i][k]+cost[k][j]);
                    time[i][j]=min(time[i][j],time[i][k]+time[k][j]);
                }
            }
        }
        int k;
        cin>>k;
        for(int i=0;i<k;++i){
            int p,q,r;
            cin>>p>>q>>r;
            p--;q--;
            if(!r)
                cout<<cost[p][q]<<endl;
            else
                cout<<time[p][q]<<endl;
        }
    }
    return 0;
}

C++: #include<cstdio>
#include<iostream>
#include<algorithm>
using namespace std;

struct edge{
	int money;
	int time;
};

int main(){
	int n, m;
	int count;
	edge G[100][100];

	while(cin >> n >> m, n || m){
		for(int i=0; i < 100; i++){
			for(int j=0; j < 100; j++){
				G[i][j].money = 100000;
				G[i][j].time = 100000;
			}
		}

		for(int i=0; i < n; i++){
			int a, b, mo, t;
			cin >> a >> b >> mo >> t;

			G[a][b].time=t;
			G[a][b].money=mo;
			G[b][a].time=t;
			G[b][a].money=mo;
		}

		for(int k=0; k < n; k++){
			for(int i=0; i < n; i++){
				for(int j=0; j < n; j++){
					G[i][j].time = min(G[i][j].time, G[i][k].time+G[k][j].time);
					G[i][j].money = min(G[i][j].money, G[i][k].money+G[k][j].money);
				}
			}
		}

		cin >> count;
		for(int i=0; i < count; i++){
			int p;
			cin >> n >> m >> p;

			if(p==1) cout << G[n][m].time << endl;
			else cout << G[n][m].money << endl;
		}
	}
	return 0;
}