#include<iostream>
#include<cstdio>
using namespace std;
const int N = 1e5 + 5;
struct tr
{
int s[2], id, p, siz;
void init(int _id, int _p)
{
id = _id, p = _p, siz = 1;
}
} tree[N];
int root, idx, id[N], poi[N];
void pushup(int p)
{
tree[p].siz = tree[tree[p].s[0]].siz + tree[tree[p].s[1]].siz + 1;
}
void rotate(int x)
{
int y = tree[x].p, z = tree[y].p;
int k = tree[y].s[1] == x;
tree[z].s[tree[z].s[1] == y] = x, tree[x].p = z;
tree[y].s[k] = tree[x].s[k ^ 1], tree[tree[x].s[k ^ 1]].p = y;
tree[x].s[k ^ 1] = y, tree[y].p = x;
pushup(y), pushup(x);
}
void splay(int x, int k)
{
while (tree[x].p != k)
{
int y = tree[x].p, z = tree[y].p;
if (z != k)
{
if ((tree[y].s[1] == x) ^ (tree[z].s[1] == y))
rotate(x);
else
rotate(y);
}
rotate(x);
}
if (!k)
root = x;
}
int build(int l, int r, int p)
{
int mid = (l + r) >> 1, u = ++idx;
poi[id[mid]] = idx;
tree[u].init(id[mid], p);
if (l < mid)
tree[u].s[0] = build(l, mid - 1, u);
if (r > mid)
tree[u].s[1] = build(mid + 1, r, u);
pushup(u);
return u;
}
int get_k(int k)
{
int u = root;
while (u)
{
if (tree[tree[u].s[0]].siz >= k)
u = tree[u].s[0];
else if (tree[tree[u].s[0]].siz + 1 == k)
return u;
else
k -= tree[tree[u].s[0]].siz + 1, u = tree[u].s[1];
}
return 0;
}
void Top(int s)
{
int u = poi[s];
splay(u, 0);
int v = get_k(tree[tree[u].s[0]].siz + 2);
if (v)
{
splay(v, u);
tree[tree[u].s[0]].p = v, tree[v].s[0] = tree[u].s[0];
tree[u].s[0] = 0;
pushup(v);
}
else
swap(tree[u].s[0], tree[u].s[1]);
}
void Bottom(int s)
{
int u = poi[s];
splay(u, 0);
int v = get_k(tree[tree[u].s[0]].siz);
if (v)
{
splay(v, u);
tree[tree[u].s[1]].p = v, tree[v].s[1] = tree[u].s[1];
tree[u].s[1] = 0;
pushup(v);
}
else
swap(tree[u].s[0], tree[u].s[1]);
}
void Insert(int s)
{
int t;
scanf("%d", &t);
int u = poi[s];
splay(u, 0);
int v = get_k(tree[tree[u].s[0]].siz + t + 1);
swap(tree[u].id, tree[v].id), swap(poi[tree[u].id], poi[tree[v].id]);
}
int Ask(int s)
{
int u = poi[s];
splay(u, 0);
return tree[tree[u].s[0]].siz;
}
int main()
{
int n, m;
scanf("%d%d", &n, &m);
for (int i = 1; i <= n; i++)
scanf("%d", &id[i]);
root = build(1, n, 0);
while (m--)
{
char op[10];
int s;
scanf("%s%d", &op, &s);
if (op[0] == 'T')
Top(s);
else if (op[0] == 'B')
Bottom(s);
else if (op[0] == 'I')
Insert(s);
else if (op[0] == 'A')
printf("%d\n", Ask(s));
else
printf("%d\n", tree[get_k(s)].id);
}
}
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