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>
#include<string>
#define int long long
using namespace std;

signed main() {
	int a, b;
	while (cin >>b>>a, a | b) {
		vector<vector<int>>cost(a, vector<int>(a, INT_MAX));
		vector<vector<int>>time(a, vector<int>(a, INT_MAX));
		for (int c = 0; c < b; c++) {
			int d, e, f, g;
			cin >> d >> e >> f >> g;
			d--; e--;
			cost[d][e] = cost[e][d] = f;
			time[d][e] = time[e][d] = g;
		}
		for (auto j : cost) {
			for (int i : j)cout << i << " ";
			cout << endl;
		}
		for (int h = 0; h < a; h++) {
			for (int i = 0; i < a; i++) {
				for (int j = 0; j < a; j++) {
					if (i == j)cost[i][j] = time[i][j] = 0;
					else {
						cost[i][j] = (cost[i][j] < cost[i][h] + cost[h][j]) ? (cost[i][j]) : (cost[i][h] + cost[h][j]);
						time[i][j] = (time[i][j] < time[i][h] + time[h][j]) ? (time[i][j]) : (time[i][h] + time[h][j]);
					}
				}
			}
		}
		for (auto j : cost) {
			for (int i : j)cout << i << " ";
			cout << endl;
		}
		int l;
		cin >> l;
		for (int r = 0; r < l; r++) {
			int x, y, z;
			cin >> x >> y >> z;
			x--; y--;
			if (z) { cout << time[x][y] << endl; }
			else { cout << cost[x][y] << endl; }
		}
	}
}

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

int d[101][101];
int t[101][101],c[101][101];
int n,m;
const int INF = 10000000;

void warshall_floyd() {

  for ( int k = 0; k <= m; k++ ) {
    for ( int i = 0; i <= m; i++ ) {
      for ( int j = 0; j <= m; j++ ) {
	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] );
      }
    }
  }

}

int main() {

 
  while ( cin >> n >> m, n || m ) {
    for ( int i = 0; i < 101; i++ ) {
      for ( int j = 0; j < 101; j++ ) {
	if ( i == j ) {
	  t[i][j] = 0;
	  c[i][j] = 0;
	} else {
	  t[i][j] = INF;
	  c[i][j] = INF;
	}
      }
    }
  
    for ( int i = 0; i  < n; i++ ) {
      int a,b,cost,time; cin >> a >> b >> cost >> time;
      t[a][b] = t[b][a] = time;
      c[a][b] = c[b][a] = cost;
    }
    warshall_floyd();
    int k; cin >> k;
    for ( int i = 0; i < k; i++ ) {
      int p,q,r; cin >> p >> q >> r;
      if ( r == 0 ) {
	cout << c[p][q] << endl;
      } else if ( r == 1) {
	cout << t[p][q] << endl;
      }
    }

  }
  return 0;
}

C++: #include <iostream>
#include <algorithm>
#include <queue>
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=(int)1e9, MAXN=128;
int C[2][MAXN][MAXN], cost[MAXN], N, M;

void dk(int p,int q,int r)
{
        priority_queue<pii,vector<pii>,greater<pii> > Q;
        Q.push(pii(0,p)); cost[p]=0;

        while(!Q.empty())
        {
                const int cc = Q.top().first, pp = Q.top().second; Q.pop();
                if(pp==q){ break; }

                rep(i,M) if(cost[pp]+C[r][pp][i]<cost[i]){ cost[i]=C[r][pp][i]+cost[pp]; Q.push(pii(cc+C[r][pp][i],i)); }
        }
}

int main()
{
        int a,b,c,d;
        cin>>N>>M;
        rep(i,M) rep(j,N) C[0][i][j]=C[1][i][j]=(i==j?0: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(cost,cost+N,INF); cin>>a>>b>>c; dk(a-1,b-1,c); cout<<cost[b-1]<<endl; }
        return 0;
}

C++: #include <iostream>
#include <queue>
using namespace std;
struct Line{
        int a;
        int b;
        int cost;
        int time;
};
int Min(int x,int y){
        return x<y?x:y;
}
#define Max 2000000000
int main(){
        int N,M;
        while(true){
                Line lines[3000];
                cin >> N >>M;
                if(N+M==0)      break;
                for(int i=0 ; i<N ; i++ ){
                        cin >> lines[i].a >> lines[i].b ;
                        cin >> lines[i].cost >> lines[i].time;
                }
                int K;
                cin >> K;
                for(int i=0 ; i<K ; i++ ){
                        int to,from,r;
                        cin >> from >> to>>r;
                        queue <int> circle;
                        circle.push(from);
                        int dp[3000];
                        for(int i=0 ; i<=M ; i++ )
                                dp[i]=Max;
                        dp[from]=0;
                        while(circle.size()!=0){
                                int now=circle.front();
                                for(int i=0 ; i<N ; i++ ){
                                        if(now==lines[i].a){
                                                int next=lines[i].b;
                                                if(!r)
                                                        dp[next]=Min(dp[next],dp[now]+lines[i].cost);
                                                else
                                                        dp[next]=Min(dp[next],dp[now]+lines[i].time);
                                                circle.push(lines[i].b);
                                        }
                                }
                                circle.pop();
                        }
                        cout << dp[to] << endl;
                }
        }
        return 0;
}