1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205 | #include <algorithm>
#include <iostream>
#include <string>
using namespace std;
constexpr int N = 8e5 + 5;
constexpr double INF = 1e18;
void decode(string& s, int len, int mask) {
for (int i = 0; i < len; ++i) {
mask = (mask * 131 + i) % len;
swap(s[i], s[mask]);
}
}
int q, n, na;
string a;
char t[N];
// SuffixBST(SGT Ver)
// 顺序加入，查询时将询问串翻转
// 以i结束的前缀，对应节点的编号为i
// 注意：不能写懒惰删除，否则可能会破坏树的结构
constexpr double alpha = 0.75;
int root;
int sz[N], L[N], R[N];
double tag[N];
int buffer_size, buffer[N];
bool cmp(int x, int y) {
if (t[x] != t[y]) return t[x] < t[y];
return tag[x - 1] < tag[y - 1];
}
void init() { root = 0; }
void new_node(int& rt, int p, double lv, double rv) {
rt = p;
sz[rt] = 1;
tag[rt] = (lv + rv) / 2;
L[rt] = R[rt] = 0;
}
void push_up(int x) {
if (!x) return;
sz[x] = sz[L[x]] + 1 + sz[R[x]];
}
bool balance(int rt) { return alpha * sz[rt] > max(sz[L[rt]], sz[R[rt]]); }
void flatten(int rt) {
if (!rt) return;
flatten(L[rt]);
buffer[++buffer_size] = rt;
flatten(R[rt]);
}
void build(int& rt, int l, int r, double lv, double rv) {
if (l > r) {
rt = 0;
return;
}
int mid = (l + r) >> 1;
double mv = (lv + rv) / 2;
rt = buffer[mid];
tag[rt] = mv;
build(L[rt], l, mid - 1, lv, mv);
build(R[rt], mid + 1, r, mv, rv);
push_up(rt);
}
void rebuild(int& rt, double lv, double rv) {
buffer_size = 0;
flatten(rt);
build(rt, 1, buffer_size, lv, rv);
}
void insert(int& rt, int p, double lv, double rv) {
if (!rt) {
new_node(rt, p, lv, rv);
return;
}
if (cmp(p, rt))
insert(L[rt], p, lv, tag[rt]);
else
insert(R[rt], p, tag[rt], rv);
push_up(rt);
if (!balance(rt)) rebuild(rt, lv, rv);
}
void remove(int& rt, int p, double lv, double rv) {
if (!rt) return;
if (rt == p) {
if (!L[rt] || !R[rt]) {
rt = (L[rt] | R[rt]);
rebuild(rt, lv, rv);
} else {
// 找到rt的前驱来替换rt
int nrt = L[rt];
while (R[nrt]) {
nrt = R[nrt];
}
remove(L[rt], nrt, lv, tag[rt]);
L[nrt] = L[rt];
R[nrt] = R[rt];
rt = nrt;
tag[rt] = (lv + rv) / 2;
}
} else {
double mv = (lv + rv) / 2;
if (cmp(p, rt))
remove(L[rt], p, lv, mv);
else
remove(R[rt], p, mv, rv);
}
push_up(rt);
if (!balance(rt)) rebuild(rt, lv, rv);
}
bool cmp1(const string& s, int len, int p) {
for (int i = 1; i <= len; ++i, --p) {
if (s[i] < t[p]) return true;
if (s[i] > t[p]) return false;
}
return false;
}
int query(int rt, const string& s, int len) {
if (!rt) return 0;
if (cmp1(s, len, rt))
return query(L[rt], s, len);
else
return sz[L[rt]] + 1 + query(R[rt], s, len);
}
void solve() {
cin.tie(nullptr)->sync_with_stdio(false);
n = 0;
cin >> q;
init();
cin >> a;
na = a.size();
a = " " + a;
for (int i = 1; i <= na; ++i) {
t[++n] = a[i];
insert(root, n, 0, INF);
}
int mask = 0;
char op[10];
for (int i = 1; i <= q; ++i) {
cin >> op;
// 三种情况分别处理
if (op[0] == 'A') { // ADD
cin >> a;
na = a.size();
decode(a, na, mask);
a = " " + a;
for (int i = 1; i <= na; ++i) {
t[++n] = a[i];
insert(root, n, 0, INF);
}
} else if (op[0] == 'D') { // DEL
int x;
cin >> x;
while (x) {
remove(root, n, 0, INF);
--n;
--x;
}
} else if (op[0] == 'Q') { // QUERY
cin >> a;
na = a.size();
decode(a, na, mask);
a = " " + a;
reverse(a.begin() + 1, a.begin() + 1 + na);
a[na + 1] = 'Z' + 1;
a[na + 2] = 0;
int ans = query(root, a, na + 1);
--a[na];
ans -= query(root, a, na + 1);
cout << ans << '\n';
mask ^= ans;
}
}
}
int main() {
solve();
return 0;
}
|
