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>
#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 j = 0; j < N; j++)
	{
		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);

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

	int Query;
	cin >> Query;

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

		if(Start == End)
		{
			cout << 0 << endl;
			continue;
		}

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

		

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

			int minValue = -1;
			int minName  = -1;
			//?¬????????????????????£???????????°???????????????¢???
			for(int n = 0; n < candidate.size(); n++)
			{
				if(candidate[n].minValue < minValue || minValue == -1)
				{
					minValue = candidate[n].minValue;
					minName = candidate[n].name;
				}  
			}
			if(candidate.size() == 0)
			{
				cout << nodesList[End - 1].minValue << endl;
				break;
			}
			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;

}

C++: #include <iostream>
#include <string>
#include <vector>
#include <algorithm>
#include <cstring>
using namespace std;

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

int N,M,K;
const int MAXN=128;
const int INF=1e9;
int G1[MAXN][MAXN];
int G2[MAXN][MAXN];

int main()
{
	while(cin>>N>>M&&(N||M))
	{
		rep(i,N){ rep(j,N){ G1[i][j]=INF; G2[i][j]=INF; } }

		rep(i,N)
		{ 
			int a,b,c,d;
			cin>>a>>b>>c>>d; --a; --b;
			G1[a][b]=G1[b][a]=c;
			G2[a][b]=G2[b][a]=d;
		}

		rep(from,N) rep(to,N) rep(point,N)
		{
			G1[from][to] = min(G1[from][to],G1[from][point]+G1[point][to]);
			G2[from][to] = min(G2[from][to],G2[from][point]+G2[point][to]);
		}

		cin>>K;
		rep(i,K)
		{
			int a,b,c; cin>>a>>b>>c; --a; --b;
			cout<<(c?G1[a][b]:G2[a][b])<<endl;
		}
	}

	return 0;
}

C++: #include<math.h>
#include<iostream>
#define REP(i,a,b) for(i=a;i<b;i++)
#define rep(i,n) REP(i,0,n)
#define INF (1<<30)

using namespace std;

int cost[200][200], time[200][200],dist[200];
int x[200][200];
bool vis[200];
int M,N;

void dij(int p, int q, int r){
	int i,j,k,l,m,n,mn;
	rep(i,M)rep(j,M)x[i][j]= ((r==0)?(cost[i][j]):(time[i][j]));
	rep(i,M)vis[i]=false,dist[i]=INF;
	dist[p-1]=0;
	for(;;){
		k=-1,mn=INF;
		rep(i,M)if(!vis[i]&&dist[i]<mn){mn=dist[i],k=i;}
		if(k==-1 || mn>=INF) break;
		if(k==q-1)break;
		vis[k]=true;
		rep(i,M)if(!vis[i])dist[i]=min(dist[i],dist[k]+x[k][i]);
	}
	cout<<dist[q-1]<<endl;
}

int main(){
	int i,j,k,l,m,n;
	
	while(cin>>N>>M){
		if((N|M)==0) break;

		rep(i,M){
			dist[i]=INF; 
		    rep(j,M){
			  if(i==j) {cost[i][j]=time[i][j]=0; continue;}
			  cost[i][j]=time[i][j]=INF;
			}
		}
		rep(i,N){
			int a,b,c,t;
			cin>>a>>b>>c>>t;
			a--; b--;
			cost[a][b]=cost[b][a]=c; time[a][b]=time[b][a]=t;
		}
		cin>>k;
		rep(i,k){
			int p,q,r;
			cin>>p>>q>>r;
			dij(p,q,r);
		}
	}
}