#include "bits/stdc++.h"
using namespace std;
#define rep(i,n) for(int (i)=0;(i)<(int)(n);++(i))
#define rer(i,l,u) for(int (i)=(int)(l);(i)<=(int)(u);++(i))
#define reu(i,l,u) for(int (i)=(int)(l);(i)<(int)(u);++(i))
static const int INF = 0x3f3f3f3f; static const long long INFL = 0x3f3f3f3f3f3f3f3fLL;
typedef vector<int> vi; typedef pair<int, int> pii; typedef vector<pair<int, int> > vpii; typedef long long ll;
template<typename T, typename U> static void amin(T &x, U y) { if(y < x) x = y; }
template<typename T, typename U> static void amax(T &x, U y) { if(x < y) x = y; }

int main() {
	long long N;
	while(~scanf("%lld", &N)) {
		vector<int> A;
		while(N > 0) {
			A.push_back(N % 10);
			N /= 10;
		}
		reverse(A.begin(), A.end());
		int L = (int)A.size();
		vector<int> dp(1 << L, -1);
		rep(s, 1 << L) {
			int x = -1;
			rep(i, L) if(s >> i & 1)
			reu(j, i + 1, L) if(s >> j & 1)
			reu(k, j + 1, L) if(s >> k & 1) {
				if(A[i] != 0 && A[i] != A[j] && A[j] == A[k]) {
					amax(x, A[i] * 100 + A[j] * 10 + A[k] + dp[s & ~(1 << i | 1 << j | 1 << k)]);
				}
			}
			if(x == -1)
				x = 0;
			dp[s] = x;
		}
		int ans = dp.back();
		printf("%d\n", ans);
	}
	return 0;
}