BZOJ 2770: YY的Treap
平衡树中序遍历之后是个递增序列,那么 LCA 的 key 肯定加在两个节点的 key 之间
而 priority 是最小的,否则可以往上走
所以就是区间查询最值,动态开点即可
输入会有负数。。
常数较大。。
因为它的log是int大小的log。。
#include <bits/stdc++.h>
const int N = 1e5 + 7;
const int INF = 0x3f3f3f3f;
struct Node {
int pri, key;
Node(int _ = INF, int __ = 0): pri(_), key(__) {}
bool operator < (const Node &p) const {
return pri < p.pri;
}
};
struct Seg {
#define lp ch[p][0]
#define rp ch[p][1]
#define mid ((l + r) >> 1)
Node tree[N * 20];
int ch[N * 20][2];
int tol;
void pushup(int p) {
tree[p] = std::min(tree[lp], tree[rp]);
//printf("%d %d %d\n", tree[lp].pri, tree[rp].pri, tree[p].pri);
}
void update(int &p, int l, int r, int pos, int v) {
if (!p) p = ++tol;
//printf("%d %d %d\n", p, l, r);
if (l == r) {
tree[p] = Node(v, l);
//printf("%d %d %d\n", p, l, tree[p].pri);
return;
}
if (pos <= mid) update(lp, l, mid, pos, v);
else update(rp, mid + 1, r, pos, v);
pushup(p);
//printf("%d %d %d\n", l, r, tree[p].pri);
}
Node query(int p, int l, int r, int x, int y) {
//printf("%d %d %d %d\n", p, l, r, tree[p].pri);
if (x <= l && y >= r) return tree[p];
Node lans, rans;
if (x <= mid) lans = query(lp, l, mid, x, y);
if (y > mid) rans = query(rp, mid + 1, r, x, y);
return std::min(lans, rans);
}
} seg;
int ke[N], pri[N], root;
const int ALL = 1e9 + 1;
int main() {
//tree[0] = Node(INF, INF);
int n, m;
scanf("%d%d", &n, &m);
for (int i = 1; i <= n; i++)
scanf("%d", ke + i);
for (int i = 1; i <= n; i++)
scanf("%d", pri + i);
for (int i = 1; i <= n; i++)
seg.update(root, -ALL, ALL, ke[i], pri[i]);
for (int l, r; m--; ) {
static char s[10];
scanf("%s", s);
if (s[0] == 'I') {
scanf("%d%d", &l, &r);
seg.update(root, -ALL, ALL, l, r);
} else if (s[0] == 'D') {
scanf("%d", &l);
seg.update(root, -ALL, ALL, l, INF);
} else {
scanf("%d%d", &l, &r);
if (l > r) std::swap(l, r);
printf("%d\n", seg.query(root, -ALL, ALL, l, r).key);
}
}
return 0;
}