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 <bits/stdc++.h>
using namespace std;

const int INF = 1e+9;
int d[300][300], t[300][300];

int main() {
	int n, m, q, a, b, cst, tie, r;
	cin >> n >> m;
	for(int i = 0; i < m; ++i){
		for(int j = 0; j < m; ++j){
			d[i][j] = INF;
			t[i][j] = INF;
		}
	}
	for(int i = 0; i < n; ++i){
		scanf("%d%d%d%d", &a, &b, &cst, &tie);
		a--; b--;
		d[a][b] = cst; d[b][a] = cst;
		t[a][b] = tie; t[b][a] = tie;
	}
	for(int k = 0; k < m; ++k){
		for(int i = 0; i < m; ++i){
			for(int j = 0; j < m; ++j){
				d[i][j] = min(d[i][j], d[i][k] + d[k][j]);
				t[i][j] = min(t[i][j], t[i][k] + t[k][j]);
			}
		}
	}
	cin >> q;
	for(int i = 0; i < q; ++i){
		scanf("%d%d%d", &a, &b, &r);
		a--; b--;
		if(r == 0){
			printf("%d\n", d[a][b]);
		}
		else{
			printf("%d\n", t[a][b]);
		}
	}
	return 0;
}

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

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

using namespace std;

template<class T>
class d_heap{
	static const int N_MAX=3000; // !!
	int n,d;
	T a[N_MAX];
public:
	d_heap(int d):n(0),d(d){}
	const T &find_min()const{ return a[0]; }
	void insert(const T &x){
		int u=n++;
		a[u]=x;
		while(u!=0 && a[(u-1)/d]>a[u]) swap(a[(u-1)/d],a[u]), u=(u-1)/d;
	}
	void delete_min(){
		a[0]=a[--n];
		for(int u=0;;){
			int v=u;
			for(int w=d*u+1;w<=d*u+d;w++) if(w<n && a[v]>a[w]) v=w;
			if(v==u) break;
			swap(a[v],a[u]);
			u=v;
		}
	}
	bool empty()const{ return n==0; }
	int size()const{ return n; }
};

#define define_heap d_heap< pair<int,int> > H(2);

const int INF=1<<29;

struct edge{ int v,cost1,cost2; };

int main(){
	for(int m,n;scanf("%d%d",&m,&n),n;){
		vector<edge> G[100];
		rep(i,m){
			int u,v,cost1,cost2; scanf("%d%d%d%d",&u,&v,&cost1,&cost2); u--; v--;
			G[u].push_back((edge){v,cost1,cost2});
			G[v].push_back((edge){u,cost1,cost2});
		}

		int q; scanf("%d",&q);
		while(q--){
			int s,t,type; scanf("%d%d%d",&s,&t,&type); s--; t--;

			int d[100];
			rep(u,n) d[u]=(u==s?0:INF);
			define_heap;
			H.insert(make_pair(0,s));
			while(!H.empty()){
				int d_now=H.find_min().first,u=H.find_min().second;
				H.delete_min();

				if(d[u]<d_now) continue;

				rep(i,G[u].size()){
					const edge &e=G[u][i];
					int d2=d_now+(type==0?e.cost1:e.cost2);
					if(d[e.v]>d2){
						d[e.v]=d2;
						H.insert(make_pair(d2,e.v));
					}
				}
			}

			printf("%d\n",d[t]);
		}
	}

	return 0;
}

C++: #include<stdio.h>
#include<stdlib.h>
#include<iostream>
#include<string.h>
#include<math.h>
#include<cstring>
using namespace std;
int mini(int a,int b){
	if(a<b){
		return a;
	}else{
		return b;
	}
}

int cost(int p,int q,int n,int co[][101]){
	int i,s[101],a,j,min,d[101],b;
	for(i=0;i<=n;i++){s[i]=0;d[i]=2000;}
	a=p;s[a]=1;min=1500;d[a]=0;
	for(i=1;i<=n;i++){
		for(j=1;j<=n;j++){
			d[j]= mini(d[j],d[a]+co[a][j]);
		}
		s[a]=1;b=2000;
		for(j=1;j<=n;j++){
			if(s[j]==0&&d[j]<b){
				a=j;b=d[j];
			}
		}
		s[a]=1;
	}
	return d[q];
}

int main(){
	while(1){
		int i,a=0,b=0,p,q,r,j,k,n,m,co[101][101],ti[101][101],s[101];
		for(i=0;i<101;i++){
			s[i]=0;
			for(j=0;j<101;j++){
				if(i==j){
					co[i][j]=0;
					ti[i][j]=0;
				}else{
					co[i][j]=2000;
					ti[i][j]=2000;
				}
			}
		}
		cin>>n>>m;
		if(n==0&&m==0)break;
		for(i=0;i<n;i++){
			cin>>a>>b;
			cin>>co[a][b]>>ti[a][b];
			co[b][a]=co[a][b];
			ti[b][a]=ti[a][b];
		}
		cin>>k;
		for(i=0;i<k;i++){
			cin>>p>>q>>r;
			if(r==0){
				cout<<cost(p,q,m,co)<<endl;
			}else{
				cout<<cost(p,q,m,ti)<<endl;
			}
		}
	}
    return 0;
}

C++: #include <iostream>
#include <cstdio>
#include <cstdlib>
#include <time.h>
#include <math.h>
#include <vector>
#include <queue>
#include <map>
#include <set>
#include <algorithm>
#include <iterator>
#include <sstream>
#include <string>
#include <bitset>
using namespace std;
#define FOR(I,F,N) for(int I = F; I < (int)(N); I++)
#define rep(i, n) FOR(i, 0, n)
#define FIN(V) cout<<V<<endl
#define pb push_back
#define INF (1 << 30)

template<typename T>
void remove(vector<T>& vector, unsigned int index){
vector.erase(vector.begin() + index);
}

typedef pair<int, int> P;
typedef long long ll;
typedef priority_queue<int> pq;
int StrToInt(string);
string IntToStr(int);
int dx[4] = {1, -1, 0, 0};
int dy[4] = {0, 0, 1, -1};

int cost[120][120];
int timm[120][120];
int n, m;


int main(void){
	while(cin >> n >> m, n|m){
		fill_n(*cost, 120*120, 10000000);
		fill_n(*timm, 120*120, 10000000);
		for(int i = 0; i < n; i++){
			int a, b,c,t;
			cin >> a >> b >> c >> t;
			cost[a][b] = c;
			cost[b][a] = c;
			timm[a][b] = t;
			timm[b][a] = t;
		}
		for(int k=0;k<n;++k)for(int i=0;i<n;++i)for(int j=0;j<n;++j){
			cost[i][j] = min(cost[i][j], cost[i][k] + cost[k][j]);
			timm[i][j] = min(timm[i][j], timm[i][k] + timm[k][j]);
		}
		int k;
		cin >> k;
		rep(i, k){
			int a, b, c;
			cin >> a >> b >> c;
			if(!c)
				cout << cost[a][b] << endl;
			else
				cout << timm[a][b] << endl;
		}
	}

	return 0;
}



int StrToInt(string s){
	stringstream ss;
	ss << s;
	int val;
	ss >> val;
	return val;
}
string IntToStr(int i){
	stringstream ss;
	ss << i;
	return ss.str();
}