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 <iostream>
#include <string>
#define INF (1<<21)
using namespace std;

int main(){
  int i,j,k,kk,aa,bb,n,m,a,b,d,dd,c[101][101],t[101][101],f;
  while(1){
    cin >> n >> m;
    if(n == 0 && m == 0) break;

    for(i=1;i<=m;i++){
      for(j=1;j<=m;j++){
	if(i == j){
	  c[i][j] = 0;
	  t[i][j] = 0;
	}
	else{
	  c[i][j] = INF;
	  t[i][j] = INF;
	}
      }
    }

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

    for(k=1;k<=m;k++){
      for(i=1;i<=m;i++){
	for(j=1;j<=m;j++){
if(t[i][k] >= INF || t[k][j] >= INF || c[i][k] >= INF || c[k][j] >= INF) continue; 
	  if(t[i][k] + t[k][j] > INF || c[i][k] + c[k][j] > INF) continue;
	  t[i][j] = min(t[i][j],t[i][k] + t[k][j]);
	  c[i][j] = min(c[i][j],c[i][k] + c[k][j]);
	}
      }
    }

    cin >> kk;
    for(i=0;i<kk;i++){
      cin >> aa >> bb >> f;
      if(f) cout << t[aa][bb] << endl;
      else cout << c[aa][bb] << endl;
    }

  }
  return 0;
}

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

using namespace std;

#define inf 1000000000

int n,m;
int C[101][101];
int T[101][101];

class S{
	public:
	int iti,now;
	S(){}
	S(int a,int b){iti=a;now=b;}
	bool operator < (const S &a)const{
		return now>a.now;
	}
};
int dike(int st,int en,int va){
	priority_queue<S> state;
	int sima[101];
	for(int i=0;i<101;i++){
		sima[i]=inf;
	}
	state.push(S(st,0));
	sima[st]=0;
	while(1){
		S u;
		u=state.top();
		state.pop();
		
		if(u.iti==en){
			return u.now;
		}
		
		
		for(int i=1;i<=m;i++){
			if(C[u.iti][i]==inf){
				continue;
			}
			if(u.now+C[u.iti][i] < sima[i]){
				int cost=C[u.iti][i];
				if(va==1){
					cost=T[u.iti][i];
				}
				sima[i]=u.now+cost;
				state.push(S(i,sima[i]));
			}
		}
	}
}

int main(){
	while(1){
		cin>>n>>m;
		if(n==0)break;
		for(int i=0;i<101;i++){
			for(int j=0;j<101;j++){
				C[i][j]=inf;
				T[i][j]=inf;
			}
		}
		for(int i=0;i<n;i++){
			int a,b,c,d;
			cin>>a>>b>>c>>d;
			C[a][b]=C[b][a]=c;
			T[a][b]=T[b][a]=d;
		}
		
		int l;
		cin>>l;
		for(int i=0;i<l;i++){
			int a,b,c;
			cin>>a>>b>>c;
			printf("%d\n",dike(a,b,c));
		}
	}
}

C++: #include<iostream>
#include<vector>
using namespace std;
class NextNodesData
{
public:
	int nextNodesName;
	int nextNodesMany;
	int nextNodesTime;
};
class Nodes
{
public:
	vector<NextNodesData> nextNodes;
	int name;
	int minValue;
	bool fixed;
};

int main()
{
	int N, M;
	cin >> N >> M;
	vector<Nodes> nodesList;
	for(int i = 0; i < M; i++)
	{
		Nodes nodes;
		nodes.name = i+1;
		nodesList.push_back(nodes);
	}
	for(int i = 0; i < N; i++)
	{
		int Start;
		int End;
		int Many;
		int Time;
		cin >> Start >> End >> Many >> Time;

		NextNodesData nodes;
		nodes.nextNodesName = End;
		nodes.nextNodesMany = Many;
		nodes.nextNodesTime = Time;
		nodesList[Start - 1].nextNodes.push_back(nodes);
	}

	int Query;
	cin >> Query;

	for(int i = 0; i < Query; i++) //200
	{
		for(int j = 0; j < nodesList.size(); j++)
		{
			nodesList[j].fixed = false;
		}
		int Start;
		int End;
		int mode;
		
		cin >> Start >> End;
		cin >> mode;

		nodesList[Start - 1].fixed = true;
		nodesList[Start - 1].minValue = 0;
		int nextFixedNodesName = Start;

		vector<Nodes> candidate;
		while(1)
		{
			for(int j = 0; j < nodesList[nextFixedNodesName - 1].nextNodes.size(); j++)
			{
				Nodes obj;
				obj.name = nodesList[nextFixedNodesName - 1].nextNodes[j].nextNodesName;
				if(nodesList[obj.name - 1].fixed == true)
				{
					continue;
				}
				if(mode == 0)
				{
					obj.minValue = nodesList[nextFixedNodesName - 1].minValue + nodesList[nextFixedNodesName - 1].nextNodes[j].nextNodesMany;
				}
				else
				{
					obj.minValue = nodesList[nextFixedNodesName - 1].minValue + nodesList[nextFixedNodesName - 1].nextNodes[j].nextNodesTime;
				}
				candidate.push_back(obj);				   
			}

			int minValue = 1001;
			int minName  = -1;
			for(int j = 0; j < candidate.size(); j++)
			{
				
				if(candidate[j].minValue < minValue)
				{
					minValue = candidate[j].minValue;
					minName = candidate[j].name;
				}
			}
			if(minName == End)
			{
				cout << minValue << endl;
				break;
			}
			nodesList[minName - 1].minValue = minValue;
			nodesList[minName - 1].fixed = true;
			nextFixedNodesName = minName;

			for(auto itr = candidate.begin(); itr != candidate.end();)
			{
				if(nodesList[itr->name - 1].fixed == true)
				{
					itr = candidate.erase(itr);
				}
				else
				{
					itr++;
				}
			}
		}
		

	} 

	return 0;

}