func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     ios_base::sync_with_stdio(0);     cin.tie(0);     cout.tie(0);     string second, a =  1968 ;     string rem[10];     cin >> second;     int zero = 0;     bool one = 0, six = 0, eight = 0, nine = 0;     string alt =   ;     for (int i = 0; i < second.size(); i++) {       if (second[i] ==  0 ) zero++;       if (second[i] ==  1  && one) alt += second[i];       if (second[i] ==  6  && six) alt += second[i];       if (second[i] ==  8  && eight) alt += second[i];       if (second[i] ==  9  && nine) alt += second[i];       if (second[i] ==  1 )         one = 1;       else if (second[i] ==  6 )         six = 1;       else if (second[i] ==  8 )         eight = 1;       else if (second[i] ==  9 )         nine = 1;       else if (second[i] !=  0 )         alt += second[i];     }     int t = 1, mo = 0;     for (int i = 0; i < zero; i++) {       t = (t * 10) % 7;     }     int ft = t;     do {       int m = 0;       t = ft;       for (int i = 4 - 1; i >= 0; i--) {         m = (m + t * (a[i] -  0 )) % 7;         t = (t * 10) % 7;       }       rem[m] = a;     } while (next_permutation(a.begin(), a.end()));     for (int i = alt.size() - 1; i >= 0; i--) {       mo = (mo + (alt[i] -  0 ) * t) % 7;       t = (t * 10) % 7;     }     rem[7] = rem[0];     cout << alt << rem[7 - mo];     for (int i = 0; i < zero; i++) cout << 0;     return 0;   }   