View difference between Paste ID: nTRRyU5x and h9PgTeDu

 #include <bits/stdc++.h>
 #define all(x) (x).begin(),(x).end()
 
 using namespace std;
 using ll = long long;
 
 struct pt {
     int x, y, i;
     bool operator < (const pt& o) {
         if (x != o.x) return x < o.x;
         return y < o.y;
     }
 };
 
 ll answer = 1e18;
 int ind1 = -1, ind2 = -1;
 const int MSIZE = 50505;
 pt buff[MSIZE];
 
 ll Dist(const pt& a, const pt& b) {
     return (a.x - b.x) * 1ll * (a.x - b.x) + (a.y - b.y) * 1ll * (a.y - b.y);
 }
 
 void DC(int tl, int tr, vector<pt>& arr) {
     if (tl + 1 < tr) {
         int tm = (tl + tr) / 2;
         DC(tl, tm, arr);
         DC(tm, tr, arr);
         int itr = 0;
         int xmid = arr[tm].x;
         for (int i = tl; i < tr; i++) {
             if ((xmid - arr[i].x) * 1ll * (xmid - arr[i].x) <= answer) {
                 buff[itr++] = arr[i];
             }
         }
         sort(buff, buff + itr, [&] (const pt& a, const pt& b) {
             return a.y < b.y;
         });
         for (int i = 0; i < itr; i++) {
             for (int j = 1; j <= 8 && i + j < itr; j++) {
                 if (answer > Dist(buff[i], buff[i + j])) {
                     answer = Dist(buff[i], buff[i + j]);
                     ind1 = buff[i].i;
                     ind2 = buff[i + j].i;
                 }
             }
         }
     }
 }
 
 int main() {
     ios_base::sync_with_stdio(false);
     cin.tie(nullptr);
     cout.tie(nullptr);
     int n;
     cin >> n;
     vector<pt> arr(n);
     for (int i = 0; i < n; i++) {
         int x, y;
         cin >> x >> y;
         arr[i] = pt{x, y, i};
     }
     sort(all(arr));
     DC(0, n, arr);
     if (ind1 > ind2) swap(ind1, ind2);
     cout << ind1 << ' ' << ind2 << ' ';
     cout << fixed << setprecision(6) << sqrtl((long double) (answer)) << '\n';
 }