判断出栈顺序

#include "fun.cpp"
#include <stack>
using namespace std;
stack<int> s;
int indexFlag=1;//记录已经入栈的元素
void pushStack(int end)
{
    if(indexFlag<=end)
  {


    for(int i=indexFlag;i<=end;i++)
    s.push(i);
    indexFlag=end+1;
  }
}


int main()
{


int a[]={3,2,1};


//node *p=create();
//print(p);
//cout<<countLen(p)<<endl;
//cout<<countLen(p)<<endl;
//cout<<search_data(p,1)->data;


int len=sizeof(a)/sizeof(a[0]);
for(auto i=0;i<len;i++)
   {






    pushStack(a[i]);// 模仿入栈，


    if(a[i]==s.top())s.pop();
//当栈顶和a【i】相等，继续。否则，结束，

else break;




   }


if(s.empty()) cout<<"yes";
else cout<<"no";
    return 0;
}