func_code_string: #include <bits/stdc++.h>   using namespace std;   inline int read() {     int s = 0, w = 1;     char ch = getchar();     while (ch <  0  || ch >  9 ) {       if (ch ==  - ) w = -1;       ch = getchar();     }     while (ch >=  0  && ch <=  9 ) {       s = s * 10 + ch -  0 ;       ch = getchar();     }     return s * w;   }   pair<int, int> p[200005];   set<pair<int, int> > s;   void solve(int l, int r) {     if (l >= r) return;     int mid = (l + r) >> 1;     for (int i = l; i <= r; i++)       s.insert(pair<int, int>(p[mid].first, p[i].second));     solve(l, mid);     solve(mid + 1, r);     return;   }   int n;   void init() {     n = read();     for (int i = 1; i <= n; i++) {       p[i].first = read();       p[i].second = read();       s.insert(p[i]);     }     sort(p + 1, p + n + 1);     return;   }   void solv() {     solve(1, n);     printf( %d n , (int)s.size());     for (auto i = s.begin(); i != s.end(); i++) {       printf( %d %d n , i->first, i->second);     }     return;   }   int main() {     init();     solv();     return 0;   }   