Seja o seguinte programa Java:

import java.util.*;
public class Main {
public static void main(String[] args) {
Stack<Integer> p1=new Stack<Integer>();
Stack<Integer> p2=new Stack<Integer>();
Stack<Integer> p3=new Stack<Integer>();
Stack<Integer> p4=new Stack<Integer>();

for (int i=100; i < 300; i+=50)
p1.push(i);
for (int i=70; i < 90; i+=10)
p2.push(i);
for (int i=45; i < 50; i+=2)
p3.push(i);
for( boolean x=false; !x; ) {
if (!p3.isEmpty())
p4.push(p3.pop());
else
x=true;
if (!p2.isEmpty())
p4.push(p2.pop());
else
x=x&&true;
if (!p1.isEmpty())
p4.push(p1.pop());
else
x=x&&true;
}
int val=0;
for (int i=0; i < 6; i++)
val=p4.pop();
System.out.println(val);
}
}

Quando a função main for executada, será exibido no console o valor