#include <iostream>
#include <string>
#include <vector>
#include <algorithm>
#include <utility>
#include <tuple>
#include <cstdint>
#include <cstdio>
#include <map>
#include <queue>
#include <set>
#include <stack>
#include <deque>
#include <unordered_map>
#include <unordered_set>
#include <bitset>
#include <cctype>
#include <numeric>
#include <cmath>

#define ll long long int
#define pb push_back
#define rep(i,n) for(int i=0;i<(n);i++)
#define REP(i,n) for(int i=1;i<=(n);i++)
using namespace std;

int mx8[] = {0,0,1,-1,-1,1,-1,1};
int my8[] = {-1,1,0,0,-1,-1,1,1};
int mx4[] = {1,-1,0,0};
int my4[] = {0,0,-1,1};
const int MOD = 1000000007;


int main() {
    int n, N = 0;
    cin >> n;
    rep(i,100){
        N = 0;
        for(int j = 9; j >= 0; j--){
            int p = 1;
            rep(k,j) p *= 10;
            N += n / p;
            n %= p;
        }
        n = N;
    }
    cout << n << endl;
}