Go: package main

import (
	"bufio"
	"fmt"
	"os"
	"strconv"
)

type Railway struct {
	trains trains
}

type trains []int

func main() {
	var stdin string
	var s = bufio.NewScanner(os.Stdin)

	railway := Railway{}
	for s.Scan() {
		stdin = s.Text()

		n, err := strconv.Atoi(stdin)
		if err != nil {
			continue
		}
		railway.lifo(n)
	}
}

func (r *Railway) lifo(n int) {
	if n == 0 {
		if len(r.trains) == 0 {
			return
		}
		fmt.Println(r.trains[len(r.trains)-1])
		r.trains = r.trains[:len(r.trains)-1]
	} else {
		r.trains = append(r.trains, n)
	}
}

C++: #include<iostream>
#include<vector>
#include<stdio.h>
using namespace std;
int main(){
  int train[10],n,i;
  n = 0;
  int order[100],intrain[10];
  for( i = 1;i <= 10;i++){
    train[i] = i;
  }
  for(i=0;i<100;i++)
    order[i] = 11;
  i = 0;
  while(scanf("%d",&order[i]) != EOF){i++;}
  for(i = 0;order[i] != 11;i++){
    if(order[i] != 0){
      intrain[n] = order[i]; n++;}else if(order[i] == 0){
      n--;      cout << intrain[n] << endl;}
  }
}

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

int main()
{
    int train[10]={0},n,count=0,outTrain[10],trainCount=0;
    while(scanf("%d",&n)!=EOF){
        if(n){
            for(int i=count ; i!=0 ; i--){
                train[i]=train[i-1];
            }
            train[0]=n;
            count++;
        }
        else{
            outTrain[trainCount]=train[0];
            for(int i=0 ; i<count ; i++){
                train[i]=train[i+1];
            }
            train[count]=0;
            count--;
            trainCount++;
        }
    }
    for(int i=0 ; i<trainCount ; i++){
        cout << outTrain[i] << '\n';
    }
    return 0;
}