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#include <iostream>
#include <vector>
#include <cstring>
#include <algorithm>
#include <fstream>
#include <map>
#include <stack>
using namespace std;

int main()
{
    string s;
    cin >> s;
    int l = s.size();
    int zbir = 0;
    for(int i = 0; i < l; i++) {
        zbir += (s[i] - '0');
    }
    string najgolem = "";
    for(int i = 0; i < l; i++) {
        int cifra = (s[i] - '0');
        for(int j = 0; j <= 9; j++) {
            if(i == 0 and j != 0 and cifra != j) {
                int a1 = zbir - cifra;
                a1 += j;
                if(a1 % 3 == 0) {
                    s[i] = (j + '0');
                    if(najgolem < s) {
                        najgolem = s;
                    }
                    s[i] = (cifra + '0');
                }
            }
            else if(cifra != j) {
                int a1 = zbir - cifra;
                a1 += j;
                if(a1 % 3 == 0) {
                    s[i] = (j + '0');
                    if(najgolem < s) {
                        najgolem = s;
                    }
                    s[i] = (cifra + '0');
                }
                
            }
        }
    }
    cout << najgolem << endl;
    return 0;
}

// 999
// 899