Problem: Many people are aware of DMCA – Digital Millennium Copyright Act. But another recently proposed DMCA – Digital Millennium Calculation Act – is much less known.

In this problem you need to find a root of a number according to this new DMCA law.

Input

The input contains a single integer a (1 ≤ a ≤ 1000000).

Output

Output the result – an integer number.

Examples

Input


1


Output


1


Input


81


Output


9

Solution (in CPP):

Solution:
#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef vector<int> vi;
typedef vector<ll> vl;
#define all(x)                 x.begin(),x.end()
#define allr(x)                x.rbegin(),x.rend()
#define un(ve)                 ve.resize(unique(ve.begin(),ve.end())-ve.begin())
#define watch(x)               cout<<(#x)<<" = "<<x<<"\n";
#define fx(x)                  fixed<<setprecision(x)
const double EPS = 1e-7;
const int OO = 0x3f3f3f3f;
const int Mod = 1e9 + 7;
void fast()
{
	ios_base::sync_with_stdio(false);
	cin.tie(nullptr), cout.tie(nullptr);
}
void solve()
{
	int N; cin >> N;
	N %= 9;
	if (!N)
		N = 9;
	cout << N;
}
int main()
{
	fast();
	int T = 1; //cin >> T;
	while (T--)
		solve();
}