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 <iostream>
#include <cstring>

using namespace std;

const int INF=100000;
int cost[101][101];
int tim[101][101];

int main(void){
	int n,m,a,b,c;
	while(1){
		for(a=0;a<=100;a++){
			for(b=0;b<=100;b++){
				cost[a][b]=INF;
				tim[a][b]=INF;
				if(a==b)cost[a][b]=0,tim[a][b]=0;
			}
		}
		cin >> n >> m;
		if(n==0 && m==0)break;
		for(a=0;a<n;a++){
			int f,t,co,ti;
			scanf("%d%d%d%d",&f,&t,&co,&ti);
			if(cost[f][t]>co)cost[f][t]=co,cost[t][f]=co;
			if(tim[f][t]>ti)tim[f][t]=ti,tim[t][f]=ti;
		}
		for(c=1;c<=m;c++){
			for(b=1;b<=m;b++){
				for(a=1;a<=m;a++){
					cost[a][b]=min(cost[a][b],cost[a][c]+cost[c][b]);
					tim[a][b]=min(tim[a][b],tim[a][c]+tim[c][b]);
				}
			}
		}
		cin >> n;
		for(a=0;a<n;a++){
			int d,f,t;
			scanf("%d%d%d",&f,&t,&d);
			if(d==0)printf("%d\n",cost[f][t]);
			if(d==1)printf("%d\n",tim[f][t]);
		}
	}
    return 0;
}

C++: #include <iostream>
#include <algorithm>
#include <string>
#include <vector>

using namespace std;

#define FOR(i,a,b) for(int i=(a);i<(b);++i)
#define REP(i,n)  FOR(i,0,n)
#define INF 11451400



int main(){
	int lineL, statL;
	cin >> lineL >> statL;
	long leastCosts[statL][statL];
	long leastTimes[statL][statL];
	FOR(aStat,0,statL){
		FOR(bStat,0,statL){
			if(aStat==bStat){
				leastCosts[aStat][bStat] = 0;
				leastTimes[aStat][bStat] = 0;
			}else{
				leastCosts[aStat][bStat] = INF;
				leastTimes[aStat][bStat] = INF;
			}
		}
	}

	REP(lineI,lineL){
		int naStat,nbStat,nCost,nTime;
		cin >> naStat >> nbStat >> nCost >> nTime;
		naStat -=1; nbStat -=1;
		FOR(aStat,0,statL){
			FOR(bStat,0,statL){
				leastCosts[aStat][bStat] = min(leastCosts[aStat][bStat] , leastCosts[aStat][naStat]+nCost+leastCosts[nbStat][bStat]);
				leastCosts[aStat][bStat] = min(leastCosts[aStat][bStat] , leastCosts[aStat][nbStat]+nCost+leastCosts[naStat][bStat]);
				leastTimes[aStat][bStat] = min(leastTimes[aStat][bStat] , leastTimes[aStat][naStat]+nTime+leastTimes[nbStat][bStat]);
				leastTimes[aStat][bStat] = min(leastTimes[aStat][bStat] , leastTimes[aStat][nbStat]+nTime+leastTimes[naStat][bStat]);
			}
		}
	}

	int reqL;
	cin >> reqL;
	REP(reqI,reqL){
		int aStat,bStat,costOrTime;
		cin >> aStat >> bStat >> costOrTime;
		aStat-=1;bStat-=1;
		if(costOrTime==0){cout<<leastCosts[aStat][bStat]<<endl;};
		if(costOrTime==1){cout<<leastTimes[aStat][bStat]<<endl;};
	}

	return 0;
}

C++: #include <iostream>
#include <limits.h>

using namespace std;

int m;

int dijkstra( const int data[101][101], int start, int end )
{
	int i,j,next,min;
	bool visited[101];
	int distance[101];

	for( i = 1;i <= 100;i++ ){
		visited[i] = false;
		distance[i] = INT_MAX;
	}

	distance[start] = 0; next = start;

	do{
		i = next; visited[i] = true; min = INT_MAX;
		for(j = i;j <= m;j++){
			if(visited[j]) continue;
			if(data[i][j] < INT_MAX && distance[i] + data[i][j] < distance[j]) {
				distance[j] = distance[i] + data[i][j];
			}
			if( distance[j] < min ){
				min = distance[j]; next = j;
			}
		}
	} while( min < INT_MAX );

	return distance[end];
}


int main(int argc, char const* argv[])
{
	int n,weight[101][101][2];

	while( cin >> n >> m && n != 0 && m != 0 ){
		int a,b,c,d;
		for( int i = 0;i < 101;i++ ){
			for( int j = 0;j < 101;j++ ){
				weight[i][j][0] = INT_MAX;
				weight[i][j][1] = INT_MAX;
			}
		}

		for( int i = 0;i < n;i++ ){
			cin >> a >> b >> c >> d;
			weight[a][b][0] = c;
			weight[b][a][0] = c;
			weight[a][b][1] = d;
			weight[b][a][1] = d;
		}

		cin >> n;

		for( int i = 0;i < n;i++ ){
			int data[101][101];
			int p,q,r;
			cin >> p >> q >> r;
			for( int j = 1;j < 101;j++ ){
				for( int k = 1;k <101;k++ ) data[j][k] = weight[j][k][r];
			}
			cout << dijkstra( data, p, q ) << endl;
		}
	}


	return 0;

		
}

C++: #include<cstdio>
#include<iostream>
#include<vector>
#include<algorithm>
#include<map>
#include<set>
#include<queue>
#include<string>

using namespace std;

#define rep(i,n) for(int i=0;i<int(n);i++)
#define reps(i,n) for(int i=1;i<=int(n);i++)
#define sint(i) scanf("%d",&i);
#define sintt(i,j) scanf("%d%d",&i,&j);
#define sinttt(i,j,k) scanf("%d%d%d",&i,&j,&k);
#define sintttt(i,j,k,m) scanf("%d%d%d%d",&i,&j,&k,&m);

#define INF 1010000000
int dx[]={1,0,-1,0};
int dy[]={0,1,0,-1};

int main(){
	while(1){
		int n,m;
		int time[101][101];
		int cost[101][101];
		
		rep(i,101)rep(j,101)time[i][j]=cost[i][j]=INF;
		
		sintt(n,m);
		if(n==0)break;
		rep(i,n){
			int a,b,c,d;
			sintttt(a,b,c,d);
			
			time[a][b]=d;
			time[b][a]=d;
			
			cost[a][b]=c;
			cost[b][a]=c;
		}
		
		reps(k,m){
			reps(i,m){
				reps(j,m){
					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 q;
		sint(q);
		rep(i,q){
			int a,b,c;
			sinttt(a,b,c);
			if(c==1){
				printf("%d\n",time[a][b]);
			}else{
				printf("%d\n",cost[a][b]);
			}
		}
	}
}