Problem: A robot is standing at the origin of the infinite two-dimensional plane. Each second the robot moves exactly 1 meter in one of the four cardinal directions: north, south, west, and east. For the first step the robot can choose any of the four directions, but then at the end of every second it has to turn 90 degrees left or right with respect to the direction it just moved in. For example, if the robot has just moved north or south, the next step it takes has to be either west or east, and vice versa.

The robot makes exactly n steps from its starting position according to the rules above. How many different points can the robot arrive to at the end? The final orientation of the robot can be ignored.

Input

The only line contains a single integer n (1 ≤ n ≤ 1000) — the number of steps the robot makes.

Output

Print a single integer — the number of different possible locations after exactly n steps.

Examples

Input


1


Output


4


Input


2


Output


4


Input


3


Output


12

Note

In the first sample case, the robot will end up 1 meter north, south, west, or east depending on its initial direction.

In the second sample case, the robot will always end up √{2} meters north-west, north-east, south-west, or south-east.

Solution (in CPP):

Solution:
#pragma GCC optimize("Ofast")
#pragma GCC target("avx,avx2,fma")
#pragma GCC optimization("unroll-loops")
#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define ld long double
#define pb push_back
#define mpi map<ll,ll>
#define vl vector<ll>
#define mp make_pair
#define pl pair<ll,ll>
#define forn(i,n) for(ll i=0;i<n;i++)
#define ff first
#define ss second
#define fast ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);
#define inf       1000000000000
#define MOD       1000000007

long long binpow(long long a, long long b, long long m) 
{
    a %= m;
    long long res = 1;
    while (b > 0) {
        if (b & 1)
            res = res * a % m;
        a = a * a % m;
        b >>= 1;
    }
    return res;
}

void solve()
{
    ll n;
    cin>>n;
    ll ans=pow(n,2)+4*n;
    if(n%2)
    ans=(ans+1)/2;
    else
    ans=(ans)/4;
    cout<<ans+1;
}

int main() {

    int t=1;
   // cin >> t;
    while(t--) 
	{
		solve();
		cout<<endl;
    }

    return 0;
}