#include "bits/stdc++.h"
using namespace std;
#ifdef Nero
#include "Deb.h"
#else
#define deb(...)
#endif
struct SegmentTree {
struct node {
int sum, min_suf, zeros;
};
int n;
vector<node> seg;
SegmentTree (int n_) : n(n_) {
seg.resize(2 * n - 1);
}
node merge(const node& lc, const node& rc) {
node ret;
ret.sum = lc.sum + rc.sum;
ret.zeros = lc.zeros + rc.zeros;
ret.min_suf = min(rc.min_suf, rc.sum + lc.min_suf);
return ret;
}
void upd(int nd, int l, int r, int p, int v) {
if (l == r) {
seg[nd].sum = v;
seg[nd].zeros = v == 0;
seg[nd].min_suf = min(0, v);
return;
}
int mid = (l + r) >> 1;
int rs = nd + ((mid - l + 1) << 1);
if (p <= mid) {
upd(nd + 1, l, mid, p, v);
} else {
upd(rs, mid + 1, r, p, v);
}
seg[nd] = merge(seg[nd + 1], seg[rs]);
}
void upd(int p, int v) {
upd(0, 0, n - 1, p, v);
}
node qry(int nd, int l, int r, int s, int e) {
if (l >= s && r <= e) {
return seg[nd];
}
int mid = (l + r) >> 1;
int rs = nd + ((mid - l + 1) << 1);
if (mid >= e) {
return qry(nd + 1, l, mid, s, e);
} else {
if (mid < s) {
return qry(rs, mid + 1, r, s, e);
} else {
return merge(qry(nd + 1, l, mid, s, e), qry(rs, mid + 1, r, s, e));
}
}
}
int qry(int l, int r) {
node ret = qry(0, 0, n - 1, l, r);
return ret.min_suf - ret.zeros;
}
};
int main(){
ios::sync_with_stdio(false);
cin.tie(nullptr);
int n;
cin >> n;
vector<int> a(n);
for (int i = 0; i < n; ++i) {
char c;
cin >> c;
a[i] = (c == 'C' ? 1 : -1);
}
set<int> se;
vector<int> nullified(n);
SegmentTree st(n);
for (int i = 0, s = 0; i < n; ++i) {
if (s + a[i] < 0) {
nullified[i] = 1;
se.insert(i);
st.upd(i, 0);
}
else {
s += a[i];
st.upd(i, a[i]);
}
}
int q;
cin >> q;
vector<vector<pair<int, int>>> qs(n);
for (int i = 0; i < q; ++i) {
int l, r;
cin >> l >> r;
--l, --r;
qs[l].emplace_back(r, i);
}
vector<int> ans(q);
for (int i = 0; i < n; ++i) {
for (auto [qr, qi] : qs[i]) {
ans[qi] = -st.qry(i, qr);
}
if (a[i] == 1) {
auto f = se.lower_bound(i);
if (f != se.end()) {
se.insert(*f - 1);
nullified[*f - 1] = 1;
st.upd(*f - 1, 0);
}
} else if (nullified[i]) {
se.erase(i);
}
}
for (int i = 0; i < q; ++i) {
cout << ans[i] << '\n';
}
return 0;
}
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
2 ms |
600 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
2 ms |
600 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
2 ms |
600 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
