#include <bits/stdc++.h>
#define pii pair<int, int>
#define x first
#define y second
using namespace std;
const int N = 1 << 19;
int n, q, ans[N];
class SegmentTree {
private:
int t[N << 1], lz[N << 1];
void push(int p, int l, int r) {
if(lz[p]) {
t[p] += lz[p];
if(l != r) lz[p << 1] += lz[p], lz[p << 1 | 1] += lz[p];
lz[p] = 0;
}
}
template<typename T>
void travel(int x, int y, const T &f, int p = 1, int l = 1, int r = n) {
push(p, l, r);
if(x > r || l > y) return;
if(x <= l && r <= y) return f(p, l, r);
int mid = (l + r) >> 1;
travel(x, y, f, p << 1, l, mid), travel(x, y, f, p << 1 | 1, mid + 1, r);
t[p] = min(t[p << 1], t[p << 1 | 1]);
}
public:
void update(int x, int y, int k) {
travel(x, y, [&](int p, int l, int r) { lz[p] += k, push(p, l, r); });
}
int query(int x, int y, int ret = 0) {
travel(x, y, [&](int p, int l, int r) { ret = min(ret, t[p]); });
return ret;
}
} tree;
char S[N];
vector<pii> Q[N];
int main() {
scanf("%d %s %d", &n, S + 1, &q);
for(int i = 1, a, b; i <= q; i++) {
scanf("%d %d", &a, &b);
Q[b].emplace_back(a, i);
}
vector<int> stk;
for(int i = 1; i <= n; i++) {
if(S[i] == 'C') {
if(!stk.empty()) tree.update(stk.back(), n, -1), stk.pop_back();
tree.update(i, n, 1);
} else stk.emplace_back(i);
for(pii p : Q[i]) {
int lhs = tree.query(p.x, i) - tree.query(p.x - 1, p.x - 1);
int rhs = (int)stk.size() - (lower_bound(stk.begin(), stk.end(), p.x) - stk.begin());
ans[p.y] = rhs - lhs;
}
}
for(int i = 1; i <= q; i++) printf("%d\n", ans[i]);
return 0;
}
Compilation message
election.cpp: In function 'int main()':
election.cpp:47:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
scanf("%d %s %d", &n, S + 1, &q);
~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~
election.cpp:49:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
scanf("%d %d", &a, &b);
~~~~~^~~~~~~~~~~~~~~~~
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
14 ms |
12800 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
14 ms |
12800 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
14 ms |
12800 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |