#include 

#include 

#include 

using namespace std;

int count=0;

void countNum(int a[],int start,int finish)

{

    //cout<finish)

      return ;

    if(a[middle]==2)

    {

        count++;

        countNum(a,start,middle-1);

        countNum(a,middle+1,finish);

        //cout<<"get here"<2)

    {

        countNum(a,start,middle-1);

    }else

    {

       countNum(a,middle+1,finish);

    }

    //return count;

}

int main()

{



    int s[1000];

    ifstream inf("1.txt");

    int i=0;

    while(!inf.eof())

        {inf>>s[i];i++;}



    //int s[]={1,2,2,2,3};

    int start=0;//,finish=NUM-1;

    countNum(s,start,i-1);

    cout<