func_code_string: #include <bits/stdc++.h>   using namespace std;   const long long maxx = 1e6 + 7;   const long long maxn = 5000 + 7;   const long long mod = 998244853;   const long long maxs = 5 * (1E5) + 7;   const long long maxm = 4e5 + 7;   const long long maxk = 1008 + 7;   const long long maxw = 100 + 7;   const long long maxh = 100 + 7;   const double pi = 3.1415926;   const long long ten = 10;   const int ooi = 1234567;   const long long ool = 1e18 + 7;   const long double eps = 1e-8;   const int apsz = 26;   vector<int> can[2][2];   int a[maxn];   int c[maxn];   int n;   void init() {     cin >> n;     for (long long i = (0); i < (n); i++) {       char ch;       cin >> ch;       c[i] = ch -  0 ;     }     for (long long i = (0); i < (n); i++) {       char ch;       cin >> ch;       a[i] = ch -  0 ;     }     for (long long i = (0); i < (n); i++) {       if (a[i] == 1 && c[i] == 1) can[1][1].push_back(i);       if (c[i] == 1 && a[i] == 0) can[1][0].push_back(i);       if (c[i] == 0 && a[i] == 0) can[0][0].push_back(i);       if (c[i] == 0 && a[i] == 1) can[0][1].push_back(i);     }   }   void solve() {     int nn = can[0][0].size();     int nc = can[1][0].size();     int na = can[0][1].size();     int nb = can[1][1].size();     int ans = -1;     int a, b, c, d;     for (b = 0; b <= nc; b++) {       for (c = 0; c <= na; c++) {         if ((nb + na - c - b) % 2) continue;         d = (nb + na - c - b) / 2;         a = n / 2 - b - c - d;         if (a <= nn && d <= nb && a >= 0 && d >= 0) {           ans = 1;           goto ED;         }       }     }   ED:     if (ans == -1) {       cout << ans << endl;       return;     }     vector<int> ta;     for (long long i = (0); i < (a); i++) ta.push_back(can[0][0][i]);     for (long long i = (0); i < (b); i++) ta.push_back(can[1][0][i]);     for (long long i = (0); i < (c); i++) ta.push_back(can[0][1][i]);     for (long long i = (0); i < (d); i++) ta.push_back(can[1][1][i]);     for (long long i = (0); i < (n / 2); i++) {       if (i) cout <<    ;       cout << ta[i] + 1;     }     cout << endl;   }   int main(void) {     ios::sync_with_stdio(false);     cout.tie(0);     cin.tie(0);     init();     solve();     return 0;   }   