poj 1442 treap

//顺序插入数字，动态查询第i大的数，每次查询i递增
//直接暴treap
#include <iostream>
#include <ctime>
#include <cstdlib>
#include <cstring>
#include <cstdio>using namespace std;#define MX 30010int size, root;
struct Node
{int l, r, key, rand_fix;int countl, countr;
}node[MX];//left  rotate
void l_rot(int &index)
{int y = node[index].r;node[index].r = node[y].l;node[index].countr = node[y].countl;node[y].l = index;node[y].countl = node[index].countl + node[index].countr + 1;index = y;
}
//right rotate
void r_rot(int &index)
{int y = node[index].l;node[index].l = node[y].r;node[index].countl = node[y].countr;node[y].r = index;node[y].countr = node[index].countl + node[index].countr + 1;index = y;
}
void insert(int &index, int nkey)
{if(index == -1){index = ++size;node[index].l = node[index].r = -1;node[index].rand_fix = rand();node[index].key = nkey;node[index].countl = node[index].countr = 0;return ;}if(nkey < node[index].key){node[index].countl++;insert(node[index].l, nkey);if(node[node[index].l].rand_fix > node[index].rand_fix)r_rot(index);}else{node[index].countr++;insert(node[index].r, nkey);if(node[node[index].r].rand_fix > node[index].rand_fix)l_rot(index);}
}
bool remove(int &index, int nkey)
{if(index == -1) return false;if(nkey < node[index].key)return remove(node[index].l, nkey);else if(nkey > node[index].key)return remove(node[index].r, nkey);if(node[index].l == -1 && node[index].r == -1)index = -1;else if(node[index].l == -1)index = node[index].r;else if(node[index].r == -1)index = node[index].l;else{if(node[node[index].l].rand_fix < node[node[index].r].rand_fix){l_rot(index);remove(node[index].l, nkey);}else{r_rot(index);remove(node[index].r, nkey);}}return true;
}
int find(int index, int count)
{if(index == -1) return -1;if(node[index].countl + 1 == count ) return node[index].key;if(node[index].l == -1) return find(node[index].r, count-1);if(node[index].countl + 1 < count)   return find(node[index].r,count - (node[index].countl+1));return find(node[index].l, count);
}void init()
{size = root = -1;srand(time(0));
}void print(int index)
{printf("%d ", node[index].key);if(node[index].l != -1) printf("left: %d ",node[node[index].l].key);if(node[index].r != -1) printf("right:%d ",node[node[index].r].key);printf("count: %d  %d\n", node[index].countl, node[index].countr);if(node[index].l != -1) print(node[index].l); if(node[index].r != -1) print(node[index].r); }int n, m;
int s[MX];
int p, c, inc;
int main()
{//freopen("1.txt", "r", stdin);init();c = 0;scanf("%d %d", &m, &n);for(int i = 0;i < m;i++)scanf("%d", s+i);for(int i = 0;i < n;i++){scanf("%d", &p);while(c < p)insert(root,s[c++]);printf("%d\n", find(root,++inc));}// print(root);return 0;
}