func_code_string: #include <bits/stdc++.h>   using namespace std;   namespace {   const double PI = acos(-1.0);   }   struct Data {     int n;     int c;     vector<int> t;     Data() : c(0) {}     bool operator<(const Data& d) const { return c < d.c; }   };   int main() {     int n;     while (cin >> n) {       n *= 2;       Data d[101];       for (int i = 0; i < n; ++i) {         int x;         cin >> x;         d[x].n = x;         ++d[x].c;         d[x].t.push_back(i);       }       sort(d, d + 101);       bool f = 0;       vector<int> ans[2];       set<int> s[2];       int z[101] = {0};       for (int i = 0; i < 101; ++i) {         for (int j = 0; j < d[i].c; ++j) {           ans[f].push_back(d[i].n);           s[f].insert(d[i].n);           z[d[i].t[j]] = f;           f = !f;         }       }       cout << s[0].size() * s[1].size() << endl;       for (int i = 0; i < n; ++i) {         if (i) cout <<    ;         cout << z[i] + 1;       }       cout << endl;     }     return 0;   }   