占坑，先留个板子。
1 #include <bits/stdc++.h> 2 3 using std::min; 4 using std::max; 5 const int N = 100000 + 233; 6 int n, now, maximum, minimum, siz, ans = 0x3f3f3f3f; 7 8 inline int read() { 9 int a = 0; char c = getchar(); 10 while (!isdigit(c)) c = getchar(); 11 while (isdigit(c)) a = a * 10 + c - '0', c = getchar(); 12 return a; 13 } 14 15 class KDTree { 16 private: 17 struct Point { 18 int x[2]; 19 friend bool operator <(Point a, Point b) { 20 return a.x[now] < b.x[now]; 21 } 22 } point[N]; 23 int dis(const Point &a, const Point &b) { 24 return abs(a.x[0] - b.x[0]) + abs(a.x[1] - b.x[1]); 25 } 26 27 struct Node { 28 Node *ch[2]; 29 Point pt; 30 int mini[2], maxi[2]; 31 void redef(Point a) { 32 pt = a, mini[0] = maxi[0] = a.x[0], mini[1] = maxi[1] = a.x[1]; 33 ch[0] = ch[1] = NULL; 34 } 35 void update(Node *a) { 36 mini[0] = min(mini[0], a -> mini[0]); 37 maxi[0] = max(maxi[0], a -> maxi[0]); 38 mini[1] = min(mini[1], a -> mini[1]); 39 maxi[1] = max(maxi[1], a -> maxi[1]); 40 } 41 void pushup() { 42 if (ch[0]) update(ch[0]); 43 if (ch[1]) update(ch[1]); 44 } 45 int calc_min(Point a) { 46 return max(mini[0] - a.x[0], 0) + max(a.x[0] - maxi[0], 0) + 47 max(mini[1] - a.x[1], 0) + max(a.x[1] - maxi[1], 0); 48 } 49 int calc_max(Point a) { 50 return max(abs(a.x[0] - mini[0]), abs(a.x[0] - maxi[0])) + 51 max(abs(a.x[1] - mini[1]), abs(a.x[1] - maxi[1])); 52 } 53 } *root, node[N]; 54 void build(Node *&p, int l, int r, int d) { 55 if (l > r) return; 56 p = node + (siz++), now = d; 57 int mid = (l + r) >> 1; 58 std::nth_element(point + l, point + mid, point + r + 1); 59 p -> redef(point[mid]); 60 build(p -> ch[0], l, mid - 1, d ^ 1); 61 build(p -> ch[1], mid + 1, r, d ^ 1); 62 p -> pushup(); 63 } 64 void query_max(Node *p, Point cmp) { 65 if (p == NULL) return; 66 maximum = max(dis(p -> pt, cmp), maximum); 67 int Dis[2] = { 68 p -> ch[0] == NULL ? 0 : p -> ch[0] -> calc_max(cmp), 69 p -> ch[1] == NULL ? 0 : p -> ch[1] -> calc_max(cmp) 70 }; 71 int first = Dis[0] > Dis[1] ? 0 : 1; 72 if (Dis[first] > maximum) query_max(p -> ch[first], cmp); 73 if (Dis[first ^ 1] > maximum) query_max(p -> ch[first ^ 1], cmp); 74 } 75 void query_min(Node *p, Point cmp) { 76 if (p == NULL) return; 77 if (dis(p -> pt, cmp)) minimum = min(dis(p -> pt, cmp), minimum); 78 int Dis[2] = { 79 p -> ch[0] == NULL ? 0x3f3f3f3f : p -> ch[0] -> calc_min(cmp), 80 p -> ch[1] == NULL ? 0x3f3f3f3f : p -> ch[1] -> calc_min(cmp) 81 }; 82 int first = Dis[0] < Dis[1] ? 0 : 1; 83 if (Dis[first] < minimum) query_min(p -> ch[first], cmp); 84 if (Dis[first ^ 1] < minimum) query_min(p -> ch[first ^ 1], cmp); 85 } 86 public: 87 KDTree() { 88 for (int i = 1; i <= n; i++) 89 point[i].x[0] = read(), point[i].x[1] = read(); 90 build(root, 1, n, 0); 91 } 92 int ask_max(int id) { 93 maximum = 0, query_max(root, point[id]); 94 return maximum; 95 } 96 int ask_min(int id) { 97 minimum = 0x3f3f3f3f, query_min(root, point[id]); 98 return minimum; 99 } 100 }; 101 102 signed main() { 103 n = read(); 104 static KDTree *KDT = new KDTree(); 105 for (int i = 1; i <= n; i++) 106 ans = min(ans, KDT -> ask_max(i) - KDT -> ask_min(i)); 107 printf("%d ", ans); 108 return 0; 109 }