#include <iostream>

#include <stack>

#include <queue>

using namespace std;

bool checkSP(int in[], int out[], int n)

{

    queue<int> input;

    for(int i=;i<n;i++)

        input.push(in[i]);

    queue<int> output;

    for(int i=;i<n;i++)

        output.push(out[i]);

    stack<int> temp;

    while(!input.empty())

    {

        int elem = input.front();

        input.pop();

        if(elem == output.front())

        {

            output.pop();

            while(!temp.empty())

            {

                if(temp.top() == output.front())

                {

                    temp.pop();

                    output.pop();

                }

                else

                    break;

            }

        }

        else

            temp.push(elem);

    }

    return (input.empty()&&temp.empty());

}

int main(){

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

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

    int n = ;

    if(checkSP(input, output, n))

        cout << "YES";

    else

        cout << "NO";

    return ;

}