import java.util.ArrayList; |
public class ArrayListAsStack { |
ArrayList stack = new ArrayList(); |
public ArrayListAsStack( int n) { |
stack.ensureCapacity(n); |
} |
public void push(Object o1) { |
stack.add(o1); |
} |
public Object pop() { |
return stack.remove(stack.size() - 1 ); |
} |
public Object topEle() { |
return stack.get(stack.size() - 1 ); |
} |
public boolean isEmpty() { |
return stack.isEmpty(); |
} |
public void clean() { |
stack.clear(); |
} |
} |