第八周作业

//返回null则不合并，否则返回合并的元素
public Interger excuter(List<interger> list1,List<interger> list2){
Interger last = null;
Stack<Interger> stack1 = new Stack<Inster>();
Stack<Interger> stack2 = new Stack<Inster>();
for(int i:list1){
stack1.push(i);
}
for(int i:list2){
stack2.push(i);
}
  int sortSize = list1.size()>list2.size()?list1.size():list2.size();
for (int i = 0; i < sortSize; i++) {
  if(i == 0 ){
  	  int a = stack1.pop(); 
  		int b = stack2.pop(); 
    if(a != b){
    	//没有合并
    }
  }
  int a = stack1.pop(); 
  int b = stack2.pop();  
  if(a == b){
  last = a;
 }else{
  return last;
  }
}
return last;
}