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#include <bits/stdc++.h>
using namespace std;
struct treap {
typedef long long T;
treap *left = nullptr;
treap *right = nullptr;
int rank, items = 1;
T value;
T sum;
bool rev = false;
treap(T val = T()) : rank(rand()), value(val), sum(val) {}
inline void update() {
if (rev) {
swap(left, right);
if (left) left->rev = !left->rev;
if (right) right->rev = !right->rev;
rev = false;
}
}
};
inline int items(treap *t) { return t ? t->items : 0; }
inline int sum(treap *t) { return t ? t->sum : 0; }
inline void recalc(treap *t) {
t->items = items(t->left) + items(t->right) + 1;
t->sum = sum(t->left) + sum(t->right) + t->value;
}
pair<treap*, treap*> split(treap *t, int k) {
if (!t) return {nullptr, nullptr};
t->update();
if (items(t->left) < k) {
auto p = split(t->right, k - items(t->left) - 1);
t->right = p.first;
recalc(t);
return {t, p.second};
}
else {
auto p = split(t->left, k);
t->right = p.first;
recalc(t);
return {p.first, t};
}
}
treap* merge(treap *a, treap *b) {
if (!a) return b;
if (!b) return a;
a->update();
b->update();
if (a->rank > b->rank) {
a->right = merge(a->right, b);
recalc(a);
return a;
}
else {
b->left = merge(a, b->left);
recalc(b);
return b;
}
}
treap::T select(treap *t, int k) {
if (!t) return treap::T();
t->update();
int i = items(t->left);
if (i == k) return t->value;
else if (i > k) return select(t->left, k);
else return select(t->right, k - i - 1);
}
treap *insert (treap *t, treap::T val, int k) {
auto p = split(t, k);
return merge(merge(p.first, new treap(val)), p.second);
}
treap *erase(treap *t, int k) {
auto p1 = split(t, k);
auto p2 = split(p1.second, 1);
return merge(p1.first, p2.second);
}
treap::T sum(treap *t, int l, int r) {
auto p1 = split(t, r);
auto p2 = split(p1.first, l);
return sum(p2.second);
}
void write(treap *t) {
if (!t) return;
t->update();
write(t->left);
cout << t->value << " ";
write(t->right);
}
void destroy(treap *t) {
if (!t) return;
destroy(t->left);
destroy(t->right);
delete t;
}
treap *t = 0;
int main() {
int n;
scanf("%d", &n);
for (int i = 0; i < n; i++) {
char c;
scanf(" %c", &c);
if (c == 'I') {
int p, x;
scanf("%d%d", &p, &x);
t = insert(t, x, p);
}
if (c == 'D') {
int p;
scanf("%d", &p);
t = erase(t, p - 1);
}
if (c == 'S') {
int l, r;
scanf("%d%d", &l, &r);
printf("ans: %lld\n", sum(t, l, r));
}
cout << "Treap:\n";
write(t);
cout << "\n";
}
destroy(t);
}
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