注意输入v要在建根的前面。
1 #include <cstdio> 2 #include <iostream> 3 #include <algorithm> 4 #include <cstring> 5 #include <cmath> 6 #include <ctime> 7 #include <queue> 8 using namespace std; 9 const int maxn = 100000 + 10; 10 int tot = 0, f[maxn], n, Q, v[maxn]; 11 char cmd; 12 struct Node{ 13 int r, v, s; 14 Node* ch[2]; 15 void maintain(){ 16 s = ch[0] -> s + ch[1] -> s + 1; 17 return ; 18 } 19 }*null = new Node(), *root[maxn], nodes[maxn]; 20 queue<Node*> RAM; 21 Node* node(){ 22 Node* o; 23 if(!RAM.empty()) o = RAM.front(), RAM.pop(); 24 else o = &nodes[tot ++]; 25 return o; 26 } 27 void del(Node* &o){ 28 RAM.push(o); 29 o = null; 30 return ; 31 } 32 void init(Node* &o, int v){ 33 o -> ch[0] = o -> ch[1] = null; 34 o -> s = 1; 35 o -> r = rand(); 36 o -> v = v; 37 return ; 38 } 39 void rotate(Node* &o, int d){ 40 Node* k = o -> ch[d ^ 1]; o -> ch[d ^ 1] = k -> ch[d]; k -> ch[d] = o; 41 o -> maintain(); k -> maintain(); o = k; return ; 42 } 43 void insert(Node* &o, int v){ 44 if(o == null) o = node(), init(o, v); 45 else{ 46 int d = v > o -> v; 47 insert(o -> ch[d], v); 48 if(o -> ch[d] -> r > o -> r) rotate(o, d ^ 1); 49 else o -> maintain(); 50 } 51 return ; 52 } 53 void remove(Node* &o, int v){ 54 if(v == o -> v){ 55 if(o -> ch[0] != null && o -> ch[1] != null){ 56 int d = o -> ch[0] -> r > o -> ch[1] -> r; 57 rotate(o, d); remove(o -> ch[d], v); 58 } 59 else{ 60 Node* k = o; 61 if(o -> ch[0] != null) o = o -> ch[0]; 62 else o = o -> ch[1]; 63 del(k); 64 } 65 } 66 else remove(o -> ch[v > o -> v], v); 67 if(o != null) o -> maintain(); 68 return ; 69 } 70 void print(Node* &o){ 71 if(o == null) return ; 72 print(o -> ch[0]); 73 printf("%d ", o -> v); 74 print(o -> ch[1]); 75 return ; 76 } 77 int kth(Node* &o, int k){ 78 if(o -> s < k || k < 1) return -1; 79 if(o -> ch[0] -> s + 1 == k) return o -> v; 80 if(o -> ch[0] -> s >= k) return kth(o -> ch[0], k); 81 return kth(o -> ch[1], k - o -> ch[0] -> s - 1); 82 } 83 void merge(Node* &left, Node* &right){ 84 if(left == null) return ; 85 merge(left -> ch[0], right); 86 merge(left -> ch[1], right); 87 insert(right, left -> v); 88 del(left); return ; 89 } 90 int findset(int x){ 91 return x == f[x] ? x : f[x] = findset(f[x]); 92 } 93 void merge(int a, int b){ 94 a = findset(a); b = findset(b); 95 if(a == b) return ; 96 if(root[a] -> s > root[b] -> s) swap(a, b); 97 merge(root[a], root[b]); 98 f[a] = b; return ; 99 } 100 void read(int &x){ 101 x = 0; int sig = 1; char ch = getchar(); 102 while(!isdigit(ch)) { if(ch == '-') sig = -1; ch = getchar(); } 103 while(isdigit(ch)) x = 10 * x + ch - '0', ch = getchar(); 104 x *= sig; return ; 105 } 106 void init(){ 107 srand(time(0)); 108 null -> s = 0; 109 read(n); read(Q); 110 for(int i = 1; i <= n; i ++) read(v[i]); 111 for(int i = 1; i <= n; i ++) f[i] = i, root[i] = node(), init(root[i], v[i]); 112 return ; 113 } 114 void work(){ 115 116 return ; 117 } 118 void print(){ 119 120 return ; 121 } 122 int main(){ 123 init(); 124 work(); 125 print(); 126 return 0; 127 }