TLE in STPAR

Here is my code for STPAR ...i m getting TLE ...Plz help.... !!!

#include<iostream>
#include<stack>
#include<cstdio>
using namespace std;
int main()
{
  int n;
  while(scanf("%d",&n) && n)
    {
      stack <int> s;
      int i,count=1,flag=0,tmp;
      for(i=0;i<n;i++)
	{
	  scanf("%d",&tmp);
	  while(!s.empty() && (s.top()==count))
	    {
	      count++;
	      s.pop();
	    }
	  if(count==tmp)
	    count++;
	  else if(!s.empty() && (s.top()<tmp))
	    {
	      flag=1;
	      break;
	    }
	  else
	    s.push(tmp);
	}
      if(flag==0)
	printf("yes\n");
      else
	printf("no\n");
    }
  return 0;
}